|
Title: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 27, 2017, 01:51:41 AM So although I have steered clear of Bitmain miners in the past I figured enough people have been having issues with these miners and it's time to figure out what the heck is going wrong with them. So I'm starting yet another thread on hacking these things to either fix them or at least figure out why they blow up.
This will be under my normal license: Information should be free, skills should be paid for. Therefore as I find out stuff about these miners I'll put it here. If anyone else has thoughts or technical specs please feel free to share them. I'd rather this not turn into a general discussion on the merits of Bitmain, Bitcoin Crash, or anything else like that, will try to keep it to the technical bits. The second post will be a FAQ of most interesting stuff, and the third post will be reserved for other administrivia. On with the show. Or as I like to say: "What's the worst that could happen?" Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 27, 2017, 01:52:31 AM Reserved for FAQs.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 27, 2017, 01:52:45 AM Reserved for administrivia
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 27, 2017, 02:04:22 AM Ok, let's get started. Our latest board of the hour came in with the usual it doesn't work problem. There are a couple of types of it doesn't work:
It blows up the power supply and shorts out. It comes up but does not hash It doesn't come up. First thing to check is to see if anything is unusual about the board. In this case, not really other than the fact that the heat sinks look like they were put on by a 5 year old. I spend a lot of time aligning heat sinks on S7's to be perfectly straight to minimize airflow turbulence since these things are air cooled in small boxes. However I did notice that one was a little bit loose, could wiggle it a bit like a loose tooth. That's bad. Using the nose I could smell a bit of burned smell at that point on the board, greeeeeat...... So put the board on the preheater, warmed up the board, then used the air tools to warm up the heat sink. Not too difficult, and it came right off leaving this: https://i.imgur.com/w34ikd4.jpg Now for a close up of the chip... https://i.imgur.com/nVvNm3I.jpg And a side view of the chip. https://i.imgur.com/FF46403.jpg And a view of the heat sink itself. https://i.imgur.com/CKCmrRO.jpg Using these we can see the problem: This chips is one of the ones that does not have a heat sink on the bottom, and more importantly has only about 50% of the chip covered with the heat sink glue. From what I can see here it looks like a sloppy Bitmain job when building it led to a board that would run somewhat warm anyway. The chip itself only had 50% contact with the sink, and judging how thick that compound is it looks like the compound made a poor connection between the chip and sink. Over time the chip got warm, had a lower resistance because it is in a series string, pulled more current, more heat, and the usual failure. Bitmain should warranty this board, but it's probably out of warranty. The lack of compound on the whole chip points to a manufacturing fail. Solution: We could pull the chip, but that gets complex and I need to talk to the owner before doing that. Likewise if the SCL signal goes through every chip in the board in series, removing the chip breaks the chain and the board does not work. Drat. Wonder if bitmain will sell me a bunch of chips.... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Isaac_ on December 27, 2017, 02:26:05 AM You can order those chips on alibaba. Perhaps even aliexpress.
Could you replace said chip? If so, just replace, add thermal paste and heatsink, should be good to go. Pardon if my suggestion isn't the best, just trying to help. Know a good deal about computer hardware but this isn't my expertise. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: barmitzfit on December 27, 2017, 02:33:24 AM You can order those chips on alibaba. Perhaps even aliexpress. Could you replace said chip? If so, just replace, add thermal paste and heatsink, should be good to go. Pardon if my suggestion isn't the best, just trying to help. Know a good deal about computer hardware but this isn't my expertise. I don't think it's as simple as that. I have been researching buying ASIC chips from alibaba and noone has yet to even return a pinout diagram.. Looking at some other threads here people have been trying to find a ASIC distributor but BitFury seems to be the only one coming out with a consumer 16nm ASIC. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Isaac_ on December 27, 2017, 02:56:39 AM I could find many sellers for the bitmain chip. I asked for a bulk amount, which was about $8. I'm guessing just a few chips will be more expensive per unit, or they might want a minimum order of some amount (I hope no higher than 10).
As for pinout diagrams, it seems they would be your only real problem, shame I can't help you with that. I am pretty sure you can buy these chips though. At least for the S9. I don't know about the S7. -edit- Ah, it's an S7. I would have looked up for you on alibaba, but I can't find the specific chip? Ah, found it. It's a BM1385. Yes, one seller does seem to have it for sale. https://www.alibaba.com/product-detail/Miner-ASIC-Chips-BM1382-BM1385_60707278004.html Try contacting them. Hope it's any help. Good luck. Would help you more as barmitzfit said with the pinout chart even if you can buy the chips it seems there will be more problems. There seems to be many more retailers for the S9 chip than the S7 Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lrowland21093 on December 27, 2017, 03:37:02 AM I found the datasheet for the BM1385 chip. I am a newbie so I probably cannot post a link (though I have been reading and learning here for years).
I will try anyway... https://bits.media/images/asic-miner-antminer-s7/BM1385_Datasheet_v2.0.pdf Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: barmitzfit on December 27, 2017, 03:39:20 AM I could find many sellers for the bitmain chip. I asked for a bulk amount, which was about $8. I'm guessing just a few chips will be more expensive per unit, or they might want a minimum order of some amount (I hope no higher than 10). As for pinout diagrams, it seems they would be your only real problem, shame I can't help you with that. I am pretty sure you can buy these chips though. At least for the S9. I don't know about the S7. -edit- Ah, it's an S7. I would have looked up for you on alibaba, but I can't find the specific chip? Ah, found it. It's a BM1385. Yes, one seller does seem to have it for sale. https://www.alibaba.com/product-detail/Miner-ASIC-Chips-BM1382-BM1385_60707278004.html Try contacting them. Hope it's any help. Good luck. Would help you more as barmitzfit said with the pinout chart even if you can buy the chips it seems there will be more problems. There seems to be many more retailers for the S9 chip than the S7 The only reason I asked for a pinout was to determine if they were a scam or not. I mean, how can a company that sells these chips not have any technical information? I don't think the ASICs on alibaba are real, I see a lot of threads on here discussing how people can create their own SHA256 ASIC and most of the answers come back saying it's impossible (The equipment used to make them is in the millions). edit: I mean this from my own expierence, I contacted a few of these suppliers and they never answered after I asked for any technical documents Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 27, 2017, 04:15:30 AM It's always tricky to find hashing chips, and normally it is not the chips themselves but the supporting technology that goes foom. Usually it's either the clock crystal (S7), the power scale chip (s7) or the FETs (S7, S9) that die, Those are easy to replace.
When hashing chips go bad it normally sucks: There's possibly damage under the chip and although these are not as bad a QFN chips they are still a pain and finding a blown chip under these heat sinks is not a joy. On Avalon units the solder typically extrudes under the chip, shorting out the communication lines. On a unit with individual heat sinks like Ants, it's normally the chip that burns up. This is also a S9, not an S7. There are plenty of S7 chips, just grab a torched board and pull chips off it then re-tin and swap. C Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: dlezama on December 27, 2017, 05:40:28 AM Interesting stuff, I'll keep an eye on your progress! I guess an option is to start buying broken stuff and cannibalize spare parts. Some people around here have many broken boards, I guess they may be happy if you can get them a few Frankenstein miners out of their garbage :)
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on December 28, 2017, 12:59:26 AM Ok, let's get started. Our latest board of the hour came in with the usual it doesn't work problem. There are a couple of types of it doesn't work: It blows up the power supply and shorts out. Is there a solution that could be developed to protect the power supply? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 28, 2017, 04:50:08 AM That's an interesting question: Normally when you have a boost/buck power supply you want to size your fets for both current capacity and dwell time. Dwell time is the time the FET has to spend "on" and the amount of time it takes to turn it "off" then "on" again.
So for example if you have to step 12v down to 1v for a single chip miner you need FETs that are on 11/12th of the time to ground, and 1/12th of the time to +12. This means that the high side FETs have to switch 12 times faster than the low side ones. The transition time is when the heat occurs, because you're switching and you want that period to be as short as possible. Likewise when you turn off you have to have the gate interrupt the power flow, and that takes time/generates heat. So you want a really fast switching FET with a narrow trench and low capacitance. Problem is the best high current FETs have nice large gate junctions so they're slow. You can switch at a slower rate, but that causes a lot more ripple which has to be smoothed by the chokes and the capacitors. And THAT generates heat. This is why on the S7's they used two FETs on the high side (12v) and one FET to switch the low side. Since they were only bucking from 12v to 10.5 or so most of the time the FETs are "on" with a small amount of "off". For the S9's they seem to start at 9.5v or so, and thus added a second FET on the low side. Which might be causing problems including more heat (thus they stuck a heat sink on the back side of the FETs, surprise!) as well as more shorted FETs which short out the power supply. They should have switched to a different single FET which would have lower capacitance (capacitors in parallel add value like resistors in series) but for some reason they didn't. By the way, this seriously nailed BFL on the Monarchs. They finally went with high power high frequency FETs on the high side but you can see where they had the pads to run TO style FETs. They also had 6 phase power supplies to smooth out the current, but that meant each FET was switching 6 times as quickly. Real bitch on wheels, if they had put their engines in series instead of parallel it would have been more like the Ants and easier to design. Another side note: This is why you don't ever run an antminer at higher than 12v. Higher input voltage would just require more bucking which means more heat and the usual failures..... I think a similar problem exists in the S9's. Might explain some of the reliability problems. Fortunately replacing FETs is not hard if you have air heat and significant preheating ability to remove the FETs and reflow new ones. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on December 28, 2017, 01:10:51 PM That's an interesting question: Normally when you have a boost/buck power supply you want to size your fets for both current capacity and dwell time. Dwell time is the time the FET has to spend "on" and the amount of time it takes to turn it "off" then "on" again. So for example if you have to step 12v down to 1v for a single chip miner you need FETs that are on 11/12th of the time to ground, and 1/12th of the time to +12. This means that the high side FETs have to switch 12 times faster than the low side ones. The transition time is when the heat occurs, because you're switching and you want that period to be as short as possible. Likewise when you turn off you have to have the gate interrupt the power flow, and that takes time/generates heat. So you want a really fast switching FET with a narrow trench and low capacitance. Problem is the best high current FETs have nice large gate junctions so they're slow. You can switch at a slower rate, but that causes a lot more ripple which has to be smoothed by the chokes and the capacitors. And THAT generates heat. This is why on the S7's they used two FETs on the high side (12v) and one FET to switch the low side. Since they were only bucking from 12v to 10.5 or so most of the time the FETs are "on" with a small amount of "off". For the S9's they seem to start at 9.5v or so, and thus added a second FET on the low side. Which might be causing problems including more heat (thus they stuck a heat sink on the back side of the FETs, surprise!) as well as more shorted FETs which short out the power supply. They should have switched to a different single FET which would have lower capacitance (capacitors in parallel add value like resistors in series) but for some reason they didn't. By the way, this seriously nailed BFL on the Monarchs. They finally went with high power high frequency FETs on the high side but you can see where they had the pads to run TO style FETs. They also had 6 phase power supplies to smooth out the current, but that meant each FET was switching 6 times as quickly. Real bitch on wheels, if they had put their engines in series instead of parallel it would have been more like the Ants and easier to design. Another side note: This is why you don't ever run an antminer at higher than 12v. Higher input voltage would just require more bucking which means more heat and the usual failures..... I think a similar problem exists in the S9's. Might explain some of the reliability problems. Fortunately replacing FETs is not hard if you have air heat and significant preheating ability to remove the FETs and reflow new ones. So it's not something a simple fuse could fix... When you say air heat and preheating ability. Are you referring to a solder rework station??? I was looking at a Hakko rework station. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Sandal_Hat on December 28, 2017, 07:05:23 PM This means one way to improve it is to open it up put our own heatsink glue and cover it 100%? Hmm but messing with the board means the 6 month warranty is gone I guess. Noob here.
Do u think this is why some antminers are hotter/colder than others? It is due to the heatsink glue? Hmmm, perhaps u can buy a dead hashboard from someone and salvage some chips. One dead hashboard with some chips can help fix alot of other hashboards? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 28, 2017, 07:56:35 PM Quite possibly, this board was assembled by what I like to call a shirker. I've seen other pictures on Ebay and wondered if the sinks were loose/off, but it seems they're glued on.
It does take some time to re-mount sinks properly, you need to put a thin layer of adhesive compound on the chip, equal amount on the sink, press together and hold/align, etc. They just went whomp. As for putting sinks on the FETs, it's best to put them on the board behind the FETs. TO style chips have a nice big drain pad and are designed to pull heat *down* and not up through the gate. Putting sinks on top of the FETs pulls hte heat through the chip, you want it to go away into the board. C Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 30, 2017, 06:23:16 PM Meantime just fixed a pair of S7's that came in the door. Both had pretty burned plugs:
https://i.imgur.com/pnDyyAy.jpg And after repairs we have nice new nickel plugs... https://i.imgur.com/Sp8mtls.jpg The trick to doing a proper plug replacement is as follows: 1) preheat: You have to get the board hot enough to allow the solder to be molten for a bit, both to get the old plug off and to remove the old solder. 2) rosin solder: Has a slightly lower melting point than ROHS crap: Use it to alloy the solder on the pins, reduces the temp a lot 3) Air heat: Use to heat all the pins at once allowing you to easily remove the plugs. Then clean up the pads, flux the new plug, put in, warm up, and solder. A good preheater can make the difference. Trying to do it without one will result in damaged pads and Vias, which will not be able to conduct the proper amount of current. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: cableiso on December 31, 2017, 04:40:48 AM I could find many sellers for the bitmain chip. I asked for a bulk amount, which was about $8. I'm guessing just a few chips will be more expensive per unit, or they might want a minimum order of some amount (I hope no higher than 10). As for pinout diagrams, it seems they would be your only real problem, shame I can't help you with that. I am pretty sure you can buy these chips though. At least for the S9. I don't know about the S7. -edit- Ah, it's an S7. I would have looked up for you on alibaba, but I can't find the specific chip? Ah, found it. It's a BM1385. Yes, one seller does seem to have it for sale. https://www.alibaba.com/product-detail/Miner-ASIC-Chips-BM1382-BM1385_60707278004.html Try contacting them. Hope it's any help. Good luck. Would help you more as barmitzfit said with the pinout chart even if you can buy the chips it seems there will be more problems. There seems to be many more retailers for the S9 chip than the S7 The only reason I asked for a pinout was to determine if they were a scam or not. I mean, how can a company that sells these chips not have any technical information? I don't think the ASICs on alibaba are real, I see a lot of threads on here discussing how people can create their own SHA256 ASIC and most of the answers come back saying it's impossible (The equipment used to make them is in the millions). edit: I mean this from my own expierence, I contacted a few of these suppliers and they never answered after I asked for any technical documents +1 to this guy for asking the right questions. Who rides with Ali Baba? The 40 thieves. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Isaac_ on December 31, 2017, 09:43:43 AM On another hand, Alibaba does have seller protection, if you pay thorugh Alibaba or Paypal. I understand your skepticism, but I am equally skeptical to your skepticism. It could go either direction.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: cableiso on December 31, 2017, 01:11:03 PM Ali express has seller protection. Alibaba you're on your own to negotiate a payment in a safe format.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on December 31, 2017, 02:52:23 PM If Bitmain builds these chips and doesn't sell them, then I doubt a third-party is going to magically get the chips. It's possible they are selling stolen or bad run chips, but those would not be the kinds of things I'd want to stake my reputation on as a repair person for a client.
Back to the technical details: There are two types of S7 miners, 45 chips, and 54 chip versions. I was looking at a 54 chip version and noticed that I didn't see anything in terms of a set of FETs, power controller, or choke/inductor. That's because there isn't one: It looks like the damn thing has all the chips in a string connected directly to the +12v line. Wow. Reminds me of the old AA5 5 tube radios from the 1930's where all the tubes were plugged into the 120v ac line. The problem of course is without some sort of a modulator a transient high on the 12v line will cause a lot of current to be drawn by the board. That could make the hottest chip (which has the lowest resistance) get even hotter and explode. And good golly, what do we have here? https://i.imgur.com/fxEc8aS.jpg Yep, blown chip. Here's a close up of the scorched damage under the chip.... https://i.imgur.com/mWMTbtW.jpg And note how on the back of the board the heat sinks that are not aligned are right in front of where the bad chip was. Almost as if they were blocking cooling air which made the chip hot which made the resistance go down which pulled more current, etc..... https://i.imgur.com/51TybE0.jpg I would make a guess that the reason for failure on this board was due to airflow not getting to the heat sink on that chip due to the poor placement of the heat sinks in front of it relative to the airflow. This creates a vacuum//turbulence point which means the chip will just get hotter. With chips in series like this design it's only a matter of time before that chip gets hot enough to short and burn out. Moral: People should make sure their heat sinks are straight. It's possible this was done by someone after the unit was shipped, but since I see this on a number of bad S9 boards I'm thinking it might be a out of the box problem. Interesting. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on January 01, 2018, 02:15:30 PM If Bitmain builds these chips and doesn't sell them, then I doubt a third-party is going to magically get the chips. It's possible they are selling stolen or bad run chips, but those would not be the kinds of things I'd want to stake my reputation on as a repair person for a client. Yep, blown chip. Here's a close up of the scorched damage under the chip.... https://i.imgur.com/mWMTbtW.jpg Another good reason to keep these units fairly clean and dust-free. Not only does the accumulation of dust act as an insulator, but it also provides fuel for a fire. I picked up a used S7 and it looked like it had been run inside a barn. I wore a full on respirator to clean it. Do you think, under the right circumstances, that this could cause the whole unit to go up in flames? How well will green PCBs burn once they're in contact with flames? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Sandal_Hat on January 01, 2018, 02:40:38 PM If Bitmain builds these chips and doesn't sell them, then I doubt a third-party is going to magically get the chips. It's possible they are selling stolen or bad run chips, but those would not be the kinds of things I'd want to stake my reputation on as a repair person for a client. Yep, blown chip. Here's a close up of the scorched damage under the chip.... https://i.imgur.com/mWMTbtW.jpg Another good reason to keep these units fairly clean and dust-free. Not only does the accumulation of dust act as an insulator, but it also provides fuel for a fire. I picked up a used S7 and it looked like it had been run inside a barn. I wore a full on respirator to clean it. Do you think, under the right circumstances, that this could cause the whole unit to go up in flames? How well will green PCBs burn once they're in contact with flames? How often do u clean the antminer. U use a can of airspray right? Do u also use air filter for your room intake air? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on January 01, 2018, 03:25:57 PM Another good reason to keep these units fairly clean and dust-free. Not only does the accumulation of dust act as an insulator, but it also provides fuel for a fire. I picked up a used S7 and it looked like it had been run inside a barn. I wore a full on respirator to clean it. Yep. I have had small flames shoot out the end of one miner on the bench, it's short lived but an impressive sight. If the miner had been clogged with debris at the time it would have been a larger fire. And yes, I have gotten miners in that literally have hay and horse crap in them, seriously I can't believe someone would take a 5k unit designed for a data center and run it in a horse barn.These are designed to run in a data center.... Quote Do you think, under the right circumstances, that this could cause the whole unit to go up in flames? How well will green PCBs burn once they're in contact with flames? Possible, the question is what is on the other side of the exhaust fan. I doubt the PCB would catch fire right off the bat, but if something flammable was on the other end of the miner and the person was using one of those massive power supply busses that can feed a thousand amps into a shorted unit then yes, you might have a nice lint fire.I recommend cleaning units every few months when they get dusty. Quick minute with a vacuum cleaner will do it. And don't run them in mines or barns. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on January 01, 2018, 03:35:13 PM Gotta be careful with that vacuum cleaner though. ;)
Because of the static electricity. It is more safe to use compressed air instead. Great thread btw once again, thanks for the efforts in the hardware section! :) Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on January 01, 2018, 03:49:40 PM Another good reason to keep these units fairly clean and dust-free. Not only does the accumulation of dust act as an insulator, but it also provides fuel for a fire. I picked up a used S7 and it looked like it had been run inside a barn. I wore a full on respirator to clean it. Yep. I have had small flames shoot out the end of one miner on the bench, it's short lived but an impressive sight. If the miner had been clogged with debris at the time it would have been a larger fire. And yes, I have gotten miners in that literally have hay and horse crap in them, seriously I can't believe someone would take a 5k unit designed for a data center and run it in a horse barn.These are designed to run in a data center.... Quote Do you think, under the right circumstances, that this could cause the whole unit to go up in flames? How well will green PCBs burn once they're in contact with flames? Possible, the question is what is on the other side of the exhaust fan. I doubt the PCB would catch fire right off the bat, but if something flammable was on the other end of the miner and the person was using one of those massive power supply busses that can feed a thousand amps into a shorted unit then yes, you might have a nice lint fire.I recommend cleaning units every few months when they get dusty. Quick minute with a vacuum cleaner will do it. And don't run them in mines or barns. Yep. I had feathers and animal crap inside mine before I cleaned it. Some of the fins were completely blocked on the intake side. Unbelievable. And good point about the fuel sources in and around the miner. I've tried to remove all the fuel sources around my miners. I had a Asicminer Cube go up in flames on me and burn a small hole in the carpet. So we're on metal bakers racks in the garage now. Mine safely! Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on January 01, 2018, 04:00:05 PM How often do u clean the antminer. U use a can of airspray right? Do u also use air filter for your room intake air? I used compressed air from my air compressor. If you don't have an air compressor, you should consider purchasing one. They're extremely handy for many-a-things besides cleaning miners. Impact tools, filling tires, filling inflatable pools, dusting the interior of your car. etc etc... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: dlezama on January 01, 2018, 06:37:59 PM How often do u clean the antminer. U use a can of airspray right? Do u also use air filter for your room intake air? I used compressed air from my air compressor. If you don't have an air compressor, you should consider purchasing one. They're extremely handy for many-a-things besides cleaning miners. Impact tools, filling tires, filling inflatable pools, dusting the interior of your car. etc etc... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on January 01, 2018, 07:10:37 PM Kind of overkill to buy a compressor :) (yeah, I get it, it has other uses). I'd go for this instead: https://www.amazon.com/Dust-Off-Disposable-Compressed-Duster-Cans/dp/B00FZYT278 (https://www.amazon.com/Dust-Off-Disposable-Compressed-Duster-Cans/dp/B00FZYT278) 2 cans for 12 bucks? It'd probably take two cans per miner to do a good job. Or a pancake compressor for 99 bucks. https://www.homedepot.com/p/Porter-Cable-6-Gal-150-PSI-Portable-Electric-Pancake-Air-Compressor-C2002/203162815 Chances are, you're going to go through a ton of those cans in your lifetime using electronics. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lrowland21093 on January 01, 2018, 09:17:40 PM If you don't have a compressor, I recommend this instead of canned air:
https://www.amazon.com/XPOWER-Airrow-Multi-Use-Electric-Computer/dp/B01BI4UQK0 It won't freeze if you use it for long periods and it has a bit more flow than canned air (though maybe not as much as a compressor). Also, it doesn't run out :) Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on January 01, 2018, 09:59:28 PM I used compressed air from my air compressor. If you don't have an air compressor, you should consider purchasing one. They're extremely handy for many-a-things besides cleaning miners. Impact tools, filling tires, filling inflatable pools, dusting the interior of your car. etc etc... Oh yeah, compressed air is great. That and a pressure washer. You would not believe the amount of stuff you can do with a pressure washer, everything from cleaning the house to gutters to your shower tiles to cleaning baked on crap for a bitcoin board (just kidding)For the really messy boards I typically use air to blow off the big crap, followed by 95% isopropyl alcohol, followed by air, then alcohol, then Q-tips to get the crud out. That pretty much does it, just have to do it outside in the yard.... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Sandal_Hat on January 02, 2018, 09:10:45 AM How often do u clean the antminer. U use a can of airspray right? Do u also use air filter for your room intake air? I used compressed air from my air compressor. If you don't have an air compressor, you should consider purchasing one. They're extremely handy for many-a-things besides cleaning miners. Impact tools, filling tires, filling inflatable pools, dusting the interior of your car. etc etc... I know can of air is safe. Is there any risk of electrostatic discharge damage if use air compressor or anything other than can of air? I used compressed air from my air compressor. If you don't have an air compressor, you should consider purchasing one. They're extremely handy for many-a-things besides cleaning miners. Impact tools, filling tires, filling inflatable pools, dusting the interior of your car. etc etc... Oh yeah, compressed air is great. That and a pressure washer. You would not believe the amount of stuff you can do with a pressure washer, everything from cleaning the house to gutters to your shower tiles to cleaning baked on crap for a bitcoin board (just kidding)For the really messy boards I typically use air to blow off the big crap, followed by 95% isopropyl alcohol, followed by air, then alcohol, then Q-tips to get the crud out. That pretty much does it, just have to do it outside in the yard.... Isopropyl alcohol is safe to use without issues? Also, does this require opening the miner such that it voids warranty ? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on January 02, 2018, 11:07:17 AM I know can of air is safe. Is there any risk of electrostatic discharge damage if use air compressor or anything other than can of air? No such risk at all with compressed air. Only if you use a vacuum cleaner, there is a risk for static electricity. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Isaac_ on January 02, 2018, 12:20:55 PM Ali express has seller protection. Alibaba you're on your own to negotiate a payment in a safe format. Try to agree through Paypal, or even Payment through Alibaba. Alibaba does give you seller protection, if you don't transfer to mysterious bank account from private chat. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: uartasic on January 02, 2018, 12:46:43 PM Nice work Lightfoot, i admire your tenacity and driven curiosity.
You are correct regarding the likelihood of the ASICs being counterfeit on Alibaba. They are more than likely a generic chip with fake asic number screened over the chip. HOWEVER, if you knew who the supply chain was for them in China that would be a massive plus. I have always hated ROHS boards / solder and the cheap ass thermal adhesive compound chinese EMS use. Absolutely nasty QA and SCM of their BOMs. Buy / assemble cheap / buy twice. Although they arent cheap which is scary. Quietly watching on the sidelines mate and living vicariously through you. I almost been a decade since i fired up the METCAL last. UA Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: fanatic26 on January 02, 2018, 05:31:20 PM It's possible this was done by someone after the unit was shipped, but since I see this on a number of bad S9 boards I'm thinking it might be a out of the box problem. Interesting. Can confirm it is an out of the box problem. I have disassembled dozens of s9s while breaking the warranty seal, meaning i'm the only one since the factory to look at the hash boards, and a large number have poorly seated heat sinks. One other thing of note, to everyone saying to use an air compressor there is one warning nobody has mentioned. Air compressors can get condensation inside of the air storage tank, which is why they come with bleeder valves. Make sure that you spray something like a piece of wood down first so you can see if moisture is being sprayed out. I use something like this on my compressors: https://www.amazon.com/Neiko-30252A-Water-Separator-Outlet/dp/B002GQ3SUA/ref=pd_lpo_vtph_469_bs_lp_t_1?_encoding=UTF8&psc=1&refRID=5TFZJ8TZ5Q486ZC943VZ Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: score1more on January 03, 2018, 12:07:16 PM One other thing of note, to everyone saying to use an air compressor there is one warning nobody has mentioned. Air compressors can get condensation inside of the air storage tank, which is why they come with bleeder valves. Make sure that you spray something like a piece of wood down first so you can see if moisture is being sprayed out. I use something like this on my compressors: https://www.amazon.com/Neiko-30252A-Water-Separator-Outlet/dp/B002GQ3SUA/ref=pd_lpo_vtph_469_bs_lp_t_1?_encoding=UTF8&psc=1&refRID=5TFZJ8TZ5Q486ZC943VZ That's a good point on the compressor and condensation. Do you install quick connect fittings on this and put right before your spray nozzle (or tool) or do you install this closer to the tank? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: fanatic26 on January 03, 2018, 04:36:09 PM Just before the tool itself, I dont want any gunk going in the air tools or being sprayed on whatever im cleaning. I like the one i linked because it fits nicely in line and doesnt get in the way.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: NotFuzzyWarm on January 04, 2018, 10:58:40 PM Quote You are correct regarding the likelihood of the ASICs being counterfeit on Alibaba. There are no 'generic' chips that can be used for counterfeiting. Unlike say the USB-Serial converter chips from FTDI, mining ASIC's cannot be built up and (poorly) cloned using mask-programmed micro-processors or gate arrays.They are more than likely a generic chip with fake asic number screened over the chip. Ja, if a counterfeiter *really really* wanted make a functional SHA256D ASIC then yes the mask programmed (and dirt cheap) route could work but performance would be horrible and not even come close to what Genuine chips run. The internal physical layout of mining chips are optimized to the nth degree for maximum throughput and trying to emulate them to burn into blank gate arrays just does not work anywhere near as fast. That leaves the chips as either improperly disposed of (stolen) rejects or a relabeled other kind of chip. Either way has SCAM written all over it. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on January 05, 2018, 03:13:04 AM Thus not something to use. Meantime been working on a few more S7 boards and Titans, never dull in this world.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: sixxkilur on January 06, 2018, 06:53:15 AM Bitmain should go back to the drawing board when it comes to heat sinks. They should utilize the same type Gridseed blades use. Gridseed and others used a full aluminum block heat sink for each hashing board.
It made them very heavy but their blades were reliable and stable. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on January 06, 2018, 09:50:16 PM Those have their advantages, but I don't know if they do quite as well on airflow/heat transfer. Properly lined up individual heal sinks can dissipate a lot of heat, but when they shadow each other you get a turbulent mess.
Avalon A6's for example have a full plate heat sink and don't drop heat quite as well. I think Bitmain just needs to pay more attention to quality control. Maybe it's not such an issue when they have no competition and people are literally shoving money at them, but a crappy product is still a crappy product. And some of these seem to be lesser in terms of quality. C Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: dslr11 on January 11, 2018, 12:05:43 AM KIND OF related to this topic (Antminers breaking and then hacking them...):
I didn't realize until now that different versions of the S9 and their hashing boards MAY not be interchangeable due to the fixed frequency vs. auto tune versions, as well as other minor changes. I searched all over the net to try to figure out the version history of the S9, and what's compatible and what isn't but I came up empty. Does anyone know how the different versions of the S9 control boards and the hashing boards match up? E.g. my S9s are version 1.6. and I just bought a version 3.75 hashing board to replace a failed one, but realizing my ignorance I thought I would find out if they are compatible before I drop in the new hashing board. I think this info (like a compatibility chart) would be very useful for anyone who needs to replace a hashing board or a control board. They come up for sale on eBay every once in a while but it's better to be sure in advance if what you are buying will actually work... Any words of wisdom on this would be greatly appreciated. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: p7mining on January 20, 2018, 05:19:08 PM I have a new antminer - hashing board will start hashing and then around 8-48 hrs later one of them just stops hashing with all asics reporting healthy. - i swapped the controller cable with another hashing board and the problem followed the hashing board. I pulled the hashing board and everything looked new and aligned with no solder breaks (that i could see) - any ideas lightfoot
https://raw.githubusercontent.com/blockopsmining/minerimages/master/hashingissues.png The only way to recover it now is either a reboot, which works sometimes, or a factory reset Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on January 20, 2018, 06:06:13 PM I have a new antminer - hashing board will start hashing and then around 8-48 hrs later one of them just stops hashing with all asics reporting healthy. - i swapped the controller cable with another hashing board and the problem followed the hashing board. I pulled the hashing board and everything looked new and aligned with no solder breaks (that i could see) - any ideas lightfoot Hm. Can you watch the temps with the board running, or try moving the board to the middle and see if the problem is in the position as opposed to the board.https://raw.githubusercontent.com/blockopsmining/minerimages/master/hashingissues.png The only way to recover it now is either a reboot, which works sometimes, or a factory reset Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: p7mining on January 20, 2018, 06:56:09 PM I have several screen shot and temps are between 69-77 degrees reported at the time of the failure...i will try moving the hashing board to the middle slot now
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 02, 2018, 04:10:11 AM Anyway, been awhile, been working on things. Some thoughts about S9's:
There are 7 strings of chips in the S9, each string has 9 chips for a total of 63 total. When you power up a S9 board without any controller, the voltage between neutral and the choke should be about 9 volts or so. This is the resting voltage, and comes out to be about 1v per hashing chip. About right. Now, when the board is connected to a controller and you power up, you should see only 200mv or so while the controller boots. Thus the controller keps the FETs in a mostly off condition. Not totally off, as we shall see, but mostly off. As the unit starts to boot you will see the voltage on the choke go to about 9.5 volts, then stay there. The led on the edge should flash (this is the reset command) then flash quickly for a few seconds (loading the hashes) then go solid on once running. If you see the voltage go to 9.5, then drop to zero 7 times this is the controller trying to reset the chips. Problem is the chips are not responding, which is the most common failure. Once the strings have checked out (each time a string is checked the LED flickers briefly) the voltage goes to about 9.6v, the lights stay on, and the unit starts hashing. Note: You need solid power supplies to keep an S9 going and to let it start; if it doesn't see a solid 12v voltage it will refuse to start. Note: You need two fans running. if you have only one it will start to hash then shut down within a few seconds. Note: Slushpool works fine with S9 miners. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 03, 2018, 12:50:55 AM Other interesting things:
I'm wondering if the white data/comm plugs are being damaged and not making contact: The soldering job for those headers is really poor to be honest, and I've noticed that it seems to be easy to deform if you plug and unplug a few times. Plus when I try to reflow the solder I often find one or two pins that wiggle around when the solder is molten. Likewise on one board finger pressure on the cable is enough to have the led light to come on 7 times (when it is testing each string) and stay on for awhile. Anyone know the digi key part number for that plug? I'm thinking of pulling one and seeing what happens. Wouldn't be the first time something like this has happened...... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on February 03, 2018, 11:01:32 AM Anyone know the digi key part number for that plug? I'm thinking of pulling one and seeing what happens. Wouldn't be the first time something like this has happened...... I remembered seeing this old post by MarkAz. It is most likely some connector model manufactured by JST. Quote from: MarkAz I can't tell you the exact model, because there are literally a ton, but I can tell you who is probably the manufacturer, and that is JST - here's some of the family of products that I thought looked like close matches: https://bitcointalk.org/index.php?topic=1077661.msg11516859#msg11516859http://www.jst-mfg.com/product/detail_e.php?series=583 http://www.jst-mfg.com/product/detail_e.php?series=645 http://www.jst-mfg.com/product/detail_e.php?series=105 http://www.jst-mfg.com/product/detail_e.php?series=191 http://www.jst-mfg.com/product/detail_e.php?series=275 If you try contacting them and sending pictures, they might be able to tell you for sure... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 03, 2018, 05:32:44 PM Interesting. I took the plug off a wrecked S7 spare, then put it on this S9 I'm working on. Now the unit flashes the led 7 times then goes solid for a minute, then goes out, never hashes. This is an improvement, but not perfect. I did however clear the pins 100%, so unless we have broken vias in there this is not fully the problem.
However reflowing the pins did get one other board working, so I now have a reference point. Next step is to check all resistances to hot and ground, to see if there are differences between a good board, a sorta not working board, and a dead board. Drat. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: the_electronrancher on February 03, 2018, 06:04:02 PM The short heatsinks are soldered to the chips ground planes, meaning that after the first tier they are "hot".
Don't set a board on a metal workbench, lol. But the main point is I wanted to tell you, lightfoot, that you might measure all the backside heatsinks to get yourself a voltage map of the board. I don't agree that it's 7x9, nor that 28nm chips have a 1v core voltage - that's a little high for 28nm. Flip a board so the short sinks are up, apply 12v with the ribbon disconnected so you get the 9.6v idle voltage from DC-DC, and measure all the heatsinks. You should get a nice voltage map of the tiers which could help you debug if you get a board with blown tiers someday. PM me if your numbers aren't consistent, I can send it but since you are digging in to these devices I think it will be a useful exercise and good technique to practice. Best! Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 03, 2018, 06:58:12 PM Yep, you're right, I forgot that the bottom (power plane) heat sinks are hot (pulls heat from the chip through the board). I'll make a map, and will post that and the ground fuzzing as a start.
Ultimate question is of course what is shutting down the board? We have three items: 1) hashing chips themselves 2) Power circuitry 3) Signal and support circuitry. If it's the chip itself then it would fail either open or short. Short can be found using the map technique: Look at the voltages and find the one that reads 0 between adjacent chips. Open is easier, one string will show voltage on the first chip in the chain but no others. Finding the exact chip would then be done by measuring chip to chip resistance, one of them is going to read zero. A side question in my brain is what's the clock and signaling circuitry like: If they all share a common clock signal then a shorted chip would ground out the clock, which could be measured at the 25mhz crystal. Likewise if they daisy chain the data signal, then a shorted chip will not pass the signal or will ground it. Back to the drawing board after I get some other stuff done. I'll see if these other two boards have a dead chip. If it is a chip, then it's possible to remove with air tools and a fair bit of preheat. These look a bit easier than normal QFN chips, as they are thinner (warm up more quickly) and they have those nice big power strips on the side and center which should auto-center them. Hm. Pulling the heat sinks is not too hard, just warm up the board then use air at a lower temp to soften the glue, then pull sink then clean top of chip to remove. Do you have a pin map of the chip itself, I could hot wire a diode and try it out. 63 chips would be 9*7 or 3*3*3. So we either have 9 strings of 7 (no), 7 strings of 9 (maybe) or 3 strings of 21 (don't know about that). One way to find out.... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 03, 2018, 08:53:18 PM Ok, it's 3 strings of 21. If you follow the chips from the 3 on the left all the way around you see voltages like (all referenced to ground)
8.58, 8.15, 7.75, 7.27, 6.44, 6.02, 5.605, 5.164, 4.74, 4.2, 3.7, 3.2, 2.8, 2.4, 1.6, 1.2 .8, .4, 0. (9.1 volts at source) Or each chip pulling about .4 volts. Makes sense. Likewise it looks like the three chips are run in parallel, so you get .5 ohms from one chip to another in the three chip set. Have to think before I do a chip to chip test, I don't want my multimeter to back-feed voltage and damage anything... However when we fire up the board we get: Miner Type = S9 set_reset_allhashboard = 0x0000ffff set_reset_allhashboard = 0x00000000 set_reset_allhashboard = 0x0000ffff set_reset_allhashboard = 0x0000ffff Check chain[5] PIC fw version=0x03 Fix freq=550 Chain[5] voltage_pic=6 value=940 set_reset_allhashboard = 0x0000ffff set_reset_allhashboard = 0x00000000 Chain[J6] has 0 asic set_reset_hashboard = 0x00000020 set_reset_hashboard = 0x00000000 retry Chain[J6] has 0 asic So if the chips are not shorted then they probably are not the source of the problem. A dead shorted chip would also raise the voltages around the string and would probably blow up pretty quickly. An open chip would not be spotted by this test, as the ground planes are probably wired together and would mask an open chip. I did leave one board powered up for a bit, and the heat sinks eventually warm up. Didn't see a temp differential on the top or bottom heat sinks from sink to sink, so all engines are probably up and idle. Hm..... Next question is it's either the support chips, or the signal line is cut. But if cut, where..... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 03, 2018, 09:02:06 PM This is interesting. On one of the boards from last night's test I see that it did come up once briefly....
Code: Check chain[7] PIC fw version=0x03 Hm. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: ^.^ on February 03, 2018, 10:55:25 PM Here's one for you I think the temperature sensor on my s7 board has gone faulty. Will this stop it mining and more importantly where the hell is the damn thing, I can find it on the older boards but not on this one. Is there also a way to by pass it? Plenty of cooling so it's not going to overheat
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: the_electronrancher on February 04, 2018, 01:32:22 AM Nice work!
I had a board like that with intermittent 0 and not 0 asic. So if the chips have core vcc (which they do, your number is right) but they don't talk, what's next? They need IO vcc, they need clock, and they need an unbroken connection to rx and tx on the header. And they need to be alive, but since they came up once it's likely they are, and are just suffering an intermittent issue with one of the other items. How good's your scope? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 04, 2018, 09:19:09 PM Nice work! I had a board like that with intermittent 0 and not 0 asic. So if the chips have core vcc (which they do, your number is right) but they don't talk, what's next? We're assuming they do (well, at least 62 did); my guess is the backplane is series/parallel with all three chips in parallel on the power and ground plane as opposed to three true serial strings tied together at both ends. Nice because the power plane is more stable and uniform, bitch because an open chip would be masked by its' neighbors (although you might see this in heat maps, as the chip would not be running at idle and its partners would be a bit warmer because they are carrying more current through them to the next series of three. Hm, where is my peek....) Quote They need IO vcc, they need clock, and they need an unbroken connection to rx and tx on the header. Hm. Is each chip wired to rx/tx on the header, or do they daisy chain between the chips? There's advantages to either way, but if they were all in parallel and one chip grounded it would sink the whole line (and rx/tx would read zero). If series any one chip could sink the string if it went open. Hm.Quote And they need to be alive, but since they came up once it's likely they are, and are just suffering an intermittent issue with one of the other items. Maybe. If one of the 63 put the tx/rx signal to ground or if it broke the chain that would show up as a dead board. The question is which one is doing it?On titans as a comparison, the 4 main dies on each chip are connected to a common signal bus that can be isolated per chip by removing a 0 ohm jumper. However the hotel power and ground cannot, therefore if a die shorts hard the board is junk. If it shorts soft you can isolate the signal, and if it fails open you just have three dies running. Back to the S9, there's also a second supply on this board, looks to be a 14.5 volt supply, I was wondering if that was series shared hotel power for the hashing chips. Quote How good's your scope? Pretty good, it's an older Tektronix T922. Main problem is it's only a 15mhz scope, I should upgrade it one of these days.Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 04, 2018, 09:27:10 PM So anyway, time to break out the real fun debugging tools. As we used to say in thermodynamics, heat is the ultimate bullshit generator. Thus if you have unusual amounts of heat or lack thereof somewhere on a board, something is up.....
So let's plug our 62 chip board into a power supply with no connection to a controller board (steady voltage, nothing hashing) and then take a look at our board here under the eye of a Predator..... https://i.imgur.com/iuodL4O.jpg Look at that. Yes the chips on the inside will be warmer than the outside ones, and yes that big blob of heat is the FETs for the power supply. Normal, but what the hell is that heat blob over on the left there. It looks like one chip is not like the others..... Time to remove that heat sink and see what's going on there. It's one of the chips that doesn't have a second sink on the bottom (they have a delta V of chips without sinks, maybe airflow improvement but very stupid in a series/parallel arrangement) and see what is going on there. Mr. Thermal is your friend. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dave64 on February 05, 2018, 05:15:49 AM Hey lightfoot, my account won't let me send more that 1 pm an hour, please text me on the number I pm'ed you a few weeks ago. My zip is 74008.
Thanks, Dave Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 05, 2018, 03:10:00 PM Gotcha Dave.
In the meantime here is the predator-vision view of an S7 board that powers up the chips but doesn't hash..... https://i.imgur.com/OVChpjL.jpg Note the chips glowing normally, and the one chip glowing red. One of these things is not like the others, and in this case it's probably a shorted chip. I've pulled it for review, will swap in another chip this week and see if that fixes it. Note: The orientation of the chips is weird, they alternate 180 degrees as you go from chip to chip on the board. Probably to better line up signal pins, but a bit confusing regardless. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: mkptr on February 06, 2018, 02:37:26 PM Hey,
Sent you a pm. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: MinerMEDIC on February 06, 2018, 06:37:11 PM Speaking of nifty tools here is a video of a S9 hash board booting up and starting to hash normally. This shows a nifty little 2400W ammeter that I built with parts off of eBay. If I had a bigger power supply I could've tested all three at the same time( of course I've never actually owned three working boards, lol). Consequently this is pretty much the only way to prove beyond a doubt that your power supply is fully functional(I Actually built a dummy load out of car head lights be used for this exact purpose).
https://youtu.be/4GV7fyXKBdA Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Hazzard on February 08, 2018, 12:14:23 AM You can order those chips on alibaba. Perhaps even aliexpress. Could you replace said chip? If so, just replace, add thermal paste and heatsink, should be good to go. Pardon if my suggestion isn't the best, just trying to help. Know a good deal about computer hardware but this isn't my expertise. What is the name of the chip we need to purchase? Can you post a link to an example? I too am having issues with a miner that kills my PSUs after only half an hour. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on February 09, 2018, 06:56:43 PM Shuts down the power supply? Is it an S7 or 9?
C Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: the_electronrancher on February 09, 2018, 11:37:04 PM You can order those chips on alibaba. Perhaps even aliexpress. Could you replace said chip? If so, just replace, add thermal paste and heatsink, should be good to go. Pardon if my suggestion isn't the best, just trying to help. Know a good deal about computer hardware but this isn't my expertise. What is the name of the chip we need to purchase? Can you post a link to an example? I too am having issues with a miner that kills my PSUs after only half an hour. I can give you a link for a Taobao seller advertising fake antminer chips. No joke - he is openly selling counterfeits that other sellers will in turn resell to us. Seeing that kind of turned me off to looking for a source other than bitmain. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dave64 on February 09, 2018, 11:47:39 PM I have a 2 month old S9 that lost a chip, lightfoot has it and posted a pic of it above, since I cannot get a replacement chip, I am considering paying him to remove the 62 working chips so I can sell them for $100ea. Would there be any interest in this? I know if someone was offering to sell me a working chip for $100, I would jump on it.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: numnutz2009 on February 12, 2018, 03:38:58 PM I have a 2 month old S9 that lost a chip, lightfoot has it and posted a pic of it above, since I cannot get a replacement chip, I am considering paying him to remove the 62 working chips so I can sell them for $100ea. Would there be any interest in this? I know if someone was offering to sell me a working chip for $100, I would jump on it. lol u think a working board broken down is worth $6200?? i guess technically $6100 since one chip is bad but either way have u lost ur damn mind man?? 1 the miner is only 2 months old so repairs are covered under warranty 2 ur hopin to price gouge worse than bitmain does and u somehow think thats ok to do lol. r u payin the nice guy that did all the work $5k of that $6100?? i highly doubt it. ne one that thinks 1 miner with 3 boards is worth $18k+ is long past the point of return. jesus! Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dave64 on February 12, 2018, 03:58:44 PM Bitmain was requiring me to send the whole miner to China and other people claim it takes at least 8 weeks to get it back, plus the chip is bad because of my own fault and really shouldn't be under warranty.
Like I said before, I would be more than happy to pay you $100 for a working chip if you want to scrap your board so I don't have to. Its not gouging when people are willing to pay it happily. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on February 12, 2018, 06:32:15 PM Bitmain was requiring me to send the whole miner to China and other people claim it takes at least 8 weeks to get it back, plus the chip is bad because of my own fault and really shouldn't be under warranty. I think a good option for you is to contact MyRig (previously known as BitmainWarranty).Like I said before, I would be more than happy to pay you $100 for a working chip if you want to scrap your board so I don't have to. Its not gouging when people are willing to pay it happily. They do out-of-warranty paid repair service for Antminers. Contact them and figure out your issue and the repair service process. https://myrig.com/contacts/ (https://myrig.com/contacts/) Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: numnutz2009 on February 12, 2018, 08:56:51 PM Bitmain was requiring me to send the whole miner to China and other people claim it takes at least 8 weeks to get it back, plus the chip is bad because of my own fault and really shouldn't be under warranty. Like I said before, I would be more than happy to pay you $100 for a working chip if you want to scrap your board so I don't have to. Its not gouging when people are willing to pay it happily. bitmain has an option to send the board to a repair place in ca for in warranty repairs. even if you have to send ur whole miner in its far less than $100 if ur inside the us. as for people being happily willing to pay it...im not so sure about that one lol. bitmain warranty will repair a board for $200 or so shipped. they will charge $200 even if the chip is provided. i can remove chips from the boards if needed but i rather not price gouge the hell outta people for $100 per chip. its not right and the markup is insane especially since theres no way to guarantee that the chips removed will function properly. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dave64 on February 13, 2018, 12:55:11 AM Bitmain offered no inside USA help, even after I offered to pay for the repair, they still wanted me to ship the whole unit back to China
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on February 13, 2018, 12:56:37 AM MyRig is a separate company and not a part of Bitmain.
Did you ask them also or just Bitmain only? Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dave64 on February 13, 2018, 01:02:54 AM Just bitmain, after getting scammed by syan and almost by a few others, I find it hard to trust anyone. I took a chance with lightfoot and he is a straight up guy, but has no chips to help me get my board going.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: HagssFIN on February 13, 2018, 01:05:03 AM MyRig (previously known as BitmainWarranty) is legit, I have had few paid repairs done at their facility and you can also ask philipma1957 who has also done business with them.
Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: ccgllc on February 13, 2018, 08:09:06 PM MyRig (previously known as BitmainWarranty) is legit, I have had few paid repairs done at their facility and you can also ask philipma1957 who has also done business with them. I've also done business with them: I sent them 5 bad older fixed-frequency boards. They managed to fix 2 of them (for a reasonable fee, but it took 2+ month) and sent the other 3 back a bit worse-for-the-wear without charge. Currently they have (2) newer boards and a controller that I screwed up loading firmware on (somehow got out of sync while doing 8 at a time and managed to get the reflashing process to start twice on a single board). They have had them since December 12th. Communication feels spotty - I ask weekly how its going and unfortunately don't always get a reply. These last 2 boards were actually only a few weeks old, so under warranty, but Bitmain insisted I send the entire miner for each - meaning I would have (4) otherwise fully functional hash boards offline for a couple of months. Instead I opted to just pay the repair fee to BItmainWarranty. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: the_electronrancher on February 18, 2018, 06:51:16 AM I'll sell you a chip for $100.
Problem is, it's about 0.4mm pitch blind mount and not likely to be seated successfully without a split vision system. Also, fails are often more than one chip. Haven't read the most recent parts of this thread, but the fails I've seen cascaded over multiple tiers of chips. I'm not trying to talk you out of it, but I don't want complaints that my chip is bad just because you can't place it. Or, if you're sure it's only one chip, have the whole top tier pulled off and use one of those. If you don't adjust the pic you'll be running at 50mV overvolt for the remaining tiers.. not that big a deal Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: jfedyks on February 18, 2018, 05:08:41 PM Meantime just fixed a pair of S7's that came in the door. Both had pretty burned plugs: https://i.imgur.com/pnDyyAy.jpg And after repairs we have nice new nickel plugs... https://i.imgur.com/Sp8mtls.jpg The trick to doing a proper plug replacement is as follows: 1) preheat: You have to get the board hot enough to allow the solder to be molten for a bit, both to get the old plug off and to remove the old solder. 2) rosin solder: Has a slightly lower melting point than ROHS crap: Use it to alloy the solder on the pins, reduces the temp a lot 3) Air heat: Use to heat all the pins at once allowing you to easily remove the plugs. Then clean up the pads, flux the new plug, put in, warm up, and solder. A good preheater can make the difference. Trying to do it without one will result in damaged pads and Vias, which will not be able to conduct the proper amount of current. First, thank you for this thread it's invaluable! I recently powered down my S7 for routine maintenance and cleaning and noticed that my power connectors were fused to the white PCB headers (very similar to your photo) on 2 out of 3 boards. It was hashing fine when I shut it down and probably would have kept running if I wasn't so paranoid. I was using an old X11 board (I think v4 or v6) and there seems to be varying opinions on whether it was a surge or a if the opposite wires became exposed and "arced" (I am very new to comprehending electricity)? I found a local guy who does soldering and he's agreed to replace the 3 headers on each board for $70 USD total ($35/board) if I provided the components. I have found and ordered a bunch from this site but I am uncertain if they will definitely work. https://www.moddiy.com/products/6%252dPin-Graphics-Card-PCIe-Male-Header-Connector-%252d-90%25-Angled-%252d-Black.html (https://www.moddiy.com/products/6%252dPin-Graphics-Card-PCIe-Male-Header-Connector-%252d-90%25-Angled-%252d-Black.html) Could you please verify that this part is an acceptable replacement. Also about those nickel ones, would you mind sharing where you ordered from? And do you think the price quote I received is a fair one? (I will likely refer him to this post for your step by step instructions) If I continue down this path I may perhaps need his services again in the future. And tbh after reading this post I'm starting to think it may be time to try my hand at soldering. Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: the_electronrancher on February 20, 2018, 01:43:05 AM They are called molex mini fit jr
They are a couple bucks each from mouser or digikey, or maybe $1.00 more to upgrade to the gold finish. The ones you linked will work fine Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: lightfoot on March 07, 2018, 01:10:29 AM Meantime been busy here working on things. Here's an interesting picture: The S9 in question is dead, and oddly enough does not respond. Checking clock signals with the scope shows clock to the end of the board but not on the other side. So I pulled the back sinks and checked. Sure enough the three test points on the bottom of the board were ok, the top ones were dead.
Pulled the heat sinks, cleared off the crud, and we see this on the third chip, bottom side: https://i.imgur.com/KnkyUL4.jpg If you look carefully on the right side of the chip you see the solder doesn't look right. What happened is either a cold solder joint from the glue factory (Bitmain) or more likely the chip overheated and melted the solder out. Either way no contact, not going to work. Off to reflow-world.... Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: Dibblah on April 09, 2018, 08:32:52 PM Just in case anyone is wondering, yes, it is possible to reflow a whole board as a last ditch attempt for boards where the source of the fault is extremely tricksy.
I don't have a proper oven which can cope with the maaaaaasive thermal mass of all of the heatsinks, so this puts the board *way* outside of the reflow parameters (it takes about 15 minutes to get up to reflow). ... Take off the electrolytics and the power connectors, clean board (I use isopropyl dip), apply thinned down flux to the topside only, ensure that you are heating on a solid surface. On a completely unrelated note, the black thermal adhesive copes remarkably well with heat. The white stuff... Not so much. Completely degrades and a slight touch will knock off the heatsink. So, I now have a completely bare of heatsinks board and am desperately trying to think of a way to properly heatsink it. I may just end up oil bathing the damn thing (it's a 54 chip board, so there are no non-SMD electrolytics). If you leave the connectors on, they will survive (foil wrapped) but look unhealthily yellowed. Subtext: Don't do this, there are *far* better ways to spend your money and time. ;) Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: SpatariuM on April 22, 2018, 05:03:29 AM Hy all,
Fairly new to this forum so don't take my words as reliable. :) I recently bought a dead S9 hashboard to play around with it. (I do not own any complete miners, but a verry curios person I am :) ) It is a autotune version from March 2017. Some notes to sumarize what you all have written in the previous posts: powerwize- there is one string of 21 chips in series with 3chips in paralel for each step (63 chips total); comunicationwise- 63 chips daisychained. If one chip goes bad and pulls any clock or data line to ground, the board is dead. Same situation if a chip interupts any af these lines. Nice thing is that Bitmain has included testpads for each chip, so troubleshooting is fairly easy. O this board, powering it up by itself, does not do any good. I get 0.38v at the buck converter output. (I am thinking that by missing the 3.3v line the PIC is not powered on, so no output). Removing the heatsinks off the chips is easy if using hot air, so is scaping the leftover thermal adhesive from the chip by using a hot soldering tip. (Correct me here please) Measuring for short on the powerline steps with resistance setting on my meter is not helpfull because the chips have a verry low resistance, under 1 ohms each... I also noticed some resistor paralelled with each step of chips noted R500 wich would make measuring for shorted chips a bit harder. These boards are missing some back heatsinks near the intake fan(12 to be exact), so overheating in this area is a posible reason of failure. (The 2 changed chips on this board were located precisely in the middle of the heatsinkless area). I think I was lucky enough to buy a board that someone has allready attempted to repair, so the guy has replaced 2 chips. Unfortunately for him the resoldering process was not good, therefore some pins were not soldered to their pads. After resoldering the 2chips, all measures tell me that the board is fixed. I am now sad that I removed all the heatsinks glued to the chips, as for further tests, I will have to clean all chips and reglue the heatsinks. I have also an idea of repositioning the back heatsinks in a chess like pattern, to see if this improves cooling at the begining of the board... If only I had a controller to test it... Does anyone located within EU have a spare controller for lending it to me? Regards, Mihai Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: SpatariuM on April 23, 2018, 05:28:09 AM Question : on a working Hashboard, when powering it up with only 12v rails and not conected to a controller, is the red Tf led supposed to stay solid red?
Ca someone who poseses god miners and defect boards test this? This ,I guess, would be a quick and easy method to see wich board is defect on your machine when one board is going defect... (And give me a hint when a repair was succeful or not) A solid red Tf led could indicate wheter clock and data lines are broken between the first and last chip on the chain and could prevent people from seeing "magic smoke" when trying to test boards... Regards, Mihai Title: Re: Hacking Bitmain Antminers (S7 & S9) because man a lot of these break...... Post by: numnutz2009 on May 02, 2018, 02:23:10 PM Question : on a working Hashboard, when powering it up with only 12v rails and not conected to a controller, is the red Tf led supposed to stay solid red? Ca someone who poseses god miners and defect boards test this? This ,I guess, would be a quick and easy method to see wich board is defect on your machine when one board is going defect... (And give me a hint when a repair was succeful or not) A solid red Tf led could indicate wheter clock and data lines are broken between the first and last chip on the chain and could prevent people from seeing "magic smoke" when trying to test boards... Regards, Mihai the boards i have repaired light up when they are connected to the controller and start hashing. when a miner doesnt detect the board i look for the one without the red led on and thats the one that failed...in my case at least. i could be wrong but i think the light only comes on when the board is being checked for connection to the controller....when the chips are being checked and tuned....and finally it stays solid when the miner is actually mining away. hope this helps. |
