anyone have an idea of an alternative heat sink that can be attached to the AMT board?
If you mean top side, just follow BMch's example and use a long one. Just be sure to find a way to bolt it down so it doesn't fall off. Can anyone point to one that will work? I guess a this time it is not advisable to run AMT design without having a sufficiently large heat sink to transfer the heat. This might do it. http://www.digikey.com/product-detail/en/ATS-52230P-C2-R0/ATS1134-ND/1284848 Certainly more surface area that the ones BM/AMT used, just be sure to check its base size to get one that covers the entire top of the chip. Again, due to gravity highly suggest having the boards horizontal. |
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At least would stay on but needs at least 3x dissipation area than that support chip sink has. In free air I'd start with a guess of 5 sq. inches of surface PER-CHIP. |
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anyone have an idea of an alternative heat sink that can be attached to the AMT board?
If you mean top side, just follow BMch's example and use a long one. Just be sure to find a way to bolt it down so it doesn't fall off. |
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Probably the thermal tape was poorly applied, creating an air pocket that led to that. Usually the case from what I have seen. Considering the assembly quality in general and overall leakage of the thermal grease this is not a shock. It looked like a rushed job.
This is indeed problematic for a couple of reasons: (1) There is no screw that ensures that the heat sink has some pressure against the chip. (2) The orientation of the boards are such that the boards are vertical and therefore gravity isn't even going to work to keep the heat sinks in place. Also, I've been saying for a while now. These heatsinks are too small. Look at the designs of both Technobit and Dragon. They've got massive heat sinks on the chip side and it's okay even if the chips are all bunched together. Even the AMT system has a much larger heat sink than what we see here at AMT. I can't understand the design. These are 28nm chips running on full throttle, AMT however decides to put the smallest heat sink one can imagine! Yes, in my opinion very botched layouts. However - remember that the chips were first tested what, late Dec/early Jan? BMch and AMT had no idea of the power loads the chips would produce and had planned on it being a lot less. Technobit being a bit hobbiest-orientated had the time to deal with the real-world specs and before selling their systems had the advantage of seeing the trouble BMch ran into. Also helps that they started with 2 and 4 chip single boards to cut their teeth on. Le sigh... To answer some question points posted, one more time thermal/power design 101: Thermal flow of the A1 chip. Look at the A1 data sheet on Github. 70% goes out the bottom, through thermal vias on the board and then to the main heat sink on the backside. That leaves 30% out the top/sides. Obviously no one ran the math to know what that means for power in/sink capacity (inc airflow used)/chip temp on the top side much less what the die temp is based on the heatsinks used top & bottom along with their required airflows. I'd guess that like many non-design folks do they just thought 'big sink and a few smaller ones on top will be fine'... Physical layout - "okay even if the chips are all bunched together". No 'if'. That is how it should have been done to begin with. It makes thermal control much easier to deal with - including overtemp sensing... (is there any?) Same with clustering the Vcore buck inductors much closer to the chips not to mention more point-of-load filtering surrounding the chip cluster as Technobit uses. From the power standpoint, given the low voltages used distance between the Vcore supplies and the chips must be as minimal as possible to keep losses on the power planes/traces to an absolute minimum. The A1 spec says max core current is 20amps. It does *not* make any mention of spike loads - all processors have them and typically are over 2x the average running value. Spread out as everything is on the Bitmine-AMT boards I'd expect to see serious fluctations if anyone bothered to probe the chips power pins... Use of thermal tape - really only advised if there are no shear loads put on the heatsink. If there are (gravity, g-forces) maximum permissible temps and load values must be within the mfrg recommendations or other means to secure are needed. |
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@AMT
I understand that you were throwing out some ideas to get a feel for what people might find acceptable, but now the professional approach would be to choose which are most viable, then get out your list and your email machine, and starting at the top (lowest unfulfilled order # ) send out a n email with a detailed description of options and what each one will entail so you can get back on track and get this show on the road in the fairest possible manner.
I don't think a public forum is the place to book peoples preferences as I know of at least one customer in the upper 600's who doesn't fallow this forum and has not received any kind of response to his 3 non-harassing phone messages, left over the last several months.
if you don't plan on compensating people who have waited the longest with extra hash power at least make them your top #1 priority.
Thanks
This is a fair point. But again the simplest thing would be to just get third party miners as suggested. FYI good job for all keeping things civil. There are certain people who I will name publicly (clenell) who hate that we are having a civil discussion. He keeps pming me and apparently others about how we are "sucking AMT's dick" Mostly referring to me really. I do happen to think having a civil discussion is necessary to get results. And AMT has been more forthcoming because of it. Hopefully now tho we get actual tangible results from it. Ditto all around. As for clenell, considering he is lawyered up already he should ask them about guidance regarding the laws against cyber harassment... A 'difference of opinion' and 'Freedom of Speech' is one thing - continued targeted harassment of people over it is a whole 'nother matter and in most locations is a civil offense. Report him to the Forum Admin at least. |
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Hello everyone,
I just noticed something very very interesting. On the AMT website, there are new, more in detail pictures of the lower power miners.
1. How could they possibly sell any of these for such a high price?
2. Why would they want to try to sell more of them if no one will buy them???
3. Does this mean that they're trying to make themselves look more professional?
4. Coincraft chip page is also updated and moved to the front of the list. Maybe they want to sell out all of the chips?
What do you guys think?
Also to AMT-
If you hadn't received my last message I will go with option 1. Please confirm. Thanks. (Order #1275)
That is the same page they have had up for months. here is a wayback from a week ago http://web.archive.org/web/20140501001729/https://advancedminers.com/ , was the same when I ordered in late Feb as well. Yes the prices on it are insane but have not changed on the smaller ones in months. |
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Snippet from SirMines everyones elses business, "THEY ARENT EVEN REGISTERED AS A U.S BUSINESS! They've been using Advanced Mining Technology's name, which is an actual mining company (other business) founded in the 80's. "
They are registered in Delaware: File Number: 5341525 Incorporation Date / Formation Date: 05/29/2013
There are several companies using the name Advanced Mining Technologies shown on a quick search, one in Australia, one in India and one in Canada as well as the one in PA. So what? As long as the 1st entity to claim the name doesn't bitch is all perfectly legal.
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Is there any evidence of a 1.2THs working that is stable?
I know only of a 520 GHs system working reliably.
Bitmine will only sell systems that is below 800 GHs.
There is no evidence at this time of an AMT system that runs reliably at 1.2THs.
I am guessing that the A1 chip for now at least needs to be ran at lower speed for best stability/life. Ergo BMch's only selling 800's. Also note that the Dragon is also sold as 1-1.2TH implying they prefer the slow rate. Well, then maybe they need to bump up the # of chips per board if possible or add another blade. Say maybe 10 per-board vs 8. Hmm, wonder how that balances the GH/W figure? Maybe you can't build such a system without requiring a power draw the exceeds most residential wiring. Well, yes we *are* talking about the max per standard 110v plug/circuit... They need to emphasize that in a home setting these are what would be classified as a large appliance as far as power draw goes. Preferably use a 220v circuit like one has to if they say, buy a welder. Just how it goes. |
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Is there any evidence of a 1.2THs working that is stable?
I know only of a 520 GHs system working reliably.
Bitmine will only sell systems that is below 800 GHs.
There is no evidence at this time of an AMT system that runs reliably at 1.2THs.
I am guessing that the A1 chip for now at least needs to be ran at lower speed for best stability/life. Ergo BMch's only selling 800's. Also note that the Dragon is also sold as 1-1.2TH implying they prefer the slow rate. Well, then maybe they need to bump up the # of chips per board if possible or add another blade. Say maybe 10 per-board vs 8. Hmm, wonder how that balances the GH/W figure? |
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The pool selection point would be my concern as well. I very very much like the one I use and throwing extra horsepower at it be it hosted or my own would be marvelous...
Still prefer a miner of my own though.
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greases fine for the back side only. Top side should have a gap filler eg Fujipoly's sarcon line or again Berquist Blue to actually embed the chip so ya pull heat from every sq micron of area ya can.
Actuallly, that dynatron setup looks pretty good, only concern would be the fan life, Tip: what kind of bearing used in the fan? Sleeve bearings do not like vertical applications and give like 1/2 or less of 'rated life' when ran vertical. Look for rifled or ball bearing.
That's a ball bearing blower i believe. But the setup is a pricy, like $50 per, and we dont know about the lifespan yet either, we've had it running for a day so we want be a bit more sure than that before we decide to move on 2k dynatron sinks. One thing we've learned from Martins stuff is that if you use it a delivered you can usually get 3-6 months out of it without altering it. Also the board/program are always set to overclock, so under-clocking out of safety would be needed as well. Hmm. the only thing I don't see at the dynatron site eg http://www.dynatron-corp.com/en/product_detail_1.aspx?cv=1-4-216&id=94&in=0 is the thermal ratings... As in thermal resistance at least so you can figure out the temps vs power in. Look at Wakefield for example http://www.wakefield-vette.com/products/forced-convection.aspx complete specs so you can get a handle on chip temps vs sink size vs cfm of air needed instead of just testing what looks good.... Um poking around that Wakefield site, at these power levels you really should look at their liquid cooling ideas http://www.wakefield-vette.com/products/liquid-cooling/liquid-cold-plates.aspx That would allow a very very compact THS-dense processor package and allow moving the radiator/fans(s) to wherever the PSU bank is... Look Koolance or frozen cpu for dripless fluid connectors to use between the boards and cooling loop Just a thought considering multi-TH miners are multi-kw... |
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greases fine for the back side only. Top side should have a gap filler eg Fujipoly's sarcon line or again Berquist Blue to actually embed the chip so ya pull heat from every sq micron of area ya can.
Actuallly, that dynatron setup looks pretty good, only concern would be the fan life, Tip: what kind of bearing used in the fan? Sleeve bearings do not like vertical applications and give like 1/2 or less of 'rated life' when ran vertical. Look for rifled or ball bearings because the last thing folks running farms are going to want to do is replace a heap'o fans every couple k hours (a few months running 24x7).
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AMT: on Option-1, what would us with just the 520 ordered be getting?
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Interesting... found this in Bitmine forum: <pic snipped to save space> Notice how much bigger the heat sink is on this. Also, the customer claims that the unit blew up because the heat sink fell off. Apparently those heat sinks are very important. No wonder both Technobit and Dragon have huge heatsinks on the side of the chip. can I just cry at the ineptitude there... Bigger heat sinks good start. Still relying on thermal tape to hod the weight in a most likely vertical orientation. bzzzzt... Could have at least provided a bolt or 2 so gravity doesn't do it's thing when the heat is on. btw, most TT is rated to around 350C (but loses strength long before that) so that got pretty damn hot to be showing damage. Again, the Technobit pic of their hex miner shows Bergquist Blue thermal gap material encasing the top side of the chips/board area. http://technobit.eu/index.php?id_product=63&controller=product&id_lang=1 Also make s very fine gripper of the heatsink once it cures in 12hrs. the 4 bolts holding the fan certainly help as well... |
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No psu is fine as I am really liking my HP server ones from Amazon  Then I guess the biggest elephant in the room remaining is - time until shipping the Klondike-style option? |
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As unprofessional as this one is about to be, we'd like to get some opinions from the community because the majority of you seem to understand our situation to a degree.
<big snip>
In most cases these hypothetical options would apply to all customers as a choice. (Again we'd just like to get our client's reactions and what may seem satisfactory)
1. Receive your miner immediately - with a 1.2hash rate or maybe a bit more. Immediately being end of this week.
2. Receive a different design - which is based on individual smaller miners, not in a case per-say, but similar to a Klondike model instead. Again for the hash rate at the time of purchase.
3.Transfer to hosting - order's/miner's to hosted option with a 20% increase, electric being billed monthly or deducted from earning, which would be again be a somewhat immediate (week or so) delivery.
4. Opt in payback. For a 6 month payback program if your order is for 2 miners or less. 12 months if your order is for 3 miners or more. Receiving a check each month for the fractionated amount in suggestion or btc each month for the amount of btc you paid.
5. Receive chips + 10. ie - if your miner was a 1.2th you would receive 50 A1 chips. <- we don't expect many to choose that one and if several do then it may counter previous options.
6. Trade in for script. - If we launched sales of a 10-11k script miner with a 70m hash rate with a 7 day delivery, your orders monetary credit would be applied to that from a price point perspective. With the choice to hold that option as the price decreases in time of course.
1st, +1 to ya. To me it's the most professional thing you have presented to us here. Kudos! As to the the Klondike reference in option-2, package(s) you mean like http://klondikeminer.com/index.php?cid=2 ? Considering I'm running an Ant s1 pharm any similar package would fit in just fine. You know the S1 design, basically 2 self supporting boards/heatsinks bolted to endplates with fans. Simple & mechanically rugged. Packs very well for shipping. Stacks well on rack shelves. Works for me. Biggest question obviously is <drum roll please> What would be the ship date for my equivalent 520GH or more package(s)? The whole idea shown in the Klondike site? eg, a Raspi, router, cables, etc? To me the idea rank best to worst is: 2 1 & 3 tied, can we be sure of the miners working? 4 5,6 (tied) |
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I 2nd the motion to never pre-order. That said, random hardware thought regarding the mess over the A1, BFL's new chip, Hashfast's Golden Nonce and the others... In all the forum bits I read on them nowhere is it mentioned that test or engineering sample chips were expressly produced. It is all "We finally have chips! <insert pic of a wafer in hands> Now we have to make them work..." Ehem, Why? It is common practice to produce several design verification /engineering sample chips as part of another high volume chips wafer. When needed it is childsplay to set aside the needed area on the wafers and slip in the needed mask. The only reason not to do that is that yes it does 'cost extra' coupled with utter blind faith in the chip as 1st-designed. The ASICS being a stacked chip is irrelevant, just means more work (cost). I take it that did not happen. If Bitmine/Innosilicon, BFL and others had even made a couple dozen chips to play with and see what they really have before taking orders the mining world would be a much happier place... I do hope that the miner industry has learned from all this (though this is BFL's 2nd go at it and same results as their 65nm chip)  |
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+2 fer ya then!
Newark/Farnell and RS electronics are 2 others I sorcee from.
Night all.
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To AMT_Miners re: component shortages
Just be very very careful about picking 2nd/3rd sources for them! There is a reason there are so few prime component sources - quality and proven performance. Contrary to seemingly popular belief (at least among purchasing agents) any given component is NOT just like any other similar one from a different maker.
Properly vetted vendors of the components are to be respected and please avoid the grey-market at all costs. Counterfeit components are rife.
There may be components from 'other' sources that do the same thing but they are not necessarily really up to the task without heavy de-rating.
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^^ Gird thy loins and read through this thread from the start...
Just for the record, Order number?
Oh believe me I've read both threads...i just figured it cant hurt to try, something is better than nothing. My orders are in the low 1500's , though when i placed them i was promised specific ship dates as i was using these boxes as samples for a larger order i intended to place once i evaluated them. Right now, for me and my budget Ants are the only real game in town (got 9 of them). They are hungrier and take up more room per-TH but they can be in-hand in days either direct from China or from many different resellers. Currently around $2400-2500/TH be they S1 or S2's. |
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