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I just received some S9's, of the bunch it appears I have two dead boards. I tried different PSU's on each miner, rebooted, updated firmware etc and nothing improved. I know this is beating a dead horse around here, but any thoughts on what may be wrong? I'd like to learn to fix these myself, is there a good thread around here that covers most issues with these boards?

Here's the screen shots of my status page for each miner with a dead board:

https://i.imgur.com/jWoq8QW.jpg - How come this one isn't showing the Chain #7 stats?
https://i.imgur.com/61Yug56.jpg  - This one shows all 3 chain stats but one isn't hashing

I'm gonna try a Bitmain support ticket, I expect they will want to ship the who miner back... Recent posts suggest BitmainWarranty.com hasn't been active?

Thanks very much, I'll return the favor when I learn more about this :P

There is ZERO info as to what typically goes wrong. I too would give my eye-teeth to get a handle on it. The only general symptom usually is the Vcore regulator shutting down (red LED light on board near the PCIE sockets not lit). As to *why* -- unknown. Either the regulator itself fails or a chip or bypass cap shorts out shutting it down.

I've had two miners with the same symptoms. I made the boards work again by simply changing places with another board in the miner. I suppose it was sheer coincidence that it worked, but what can I say, it worked. So you could try this, too. Just open your miner and exchange the places of the broken board with a functioning board. Maybe it works ^^.

This is ALL based on the S7 stuff, so take it with a grain or 100 of salt.

I don't believe that, if the s9 is the same, the LED is the regulator. In the S7, the two LEDs are attached to the last chip in the chain's busy / ready lines. These indicate (along with the correct power draw) that at least some data is getting to the end chip. It does *not* mean that the hashes from the chips (or anything, really) is getting back.

I don't have any S9 boards to play with, but on the S7 you can check the 14.5v boost converter, which is (due to it being the coldest part on the board) subject to condensation. It's really easy to replace with an ebay special. I have heard people saying that this boost is only to support the end of the chain, but it doesn't seem to - the whole IO chain goes close to 0v if it's not outputting.

In terms of the IO regulation, the 14.5v is split over the entire board (3 chip sections) by a resistive divider. This then feeds the approximate IO voltages into linear regulators, which referenced to the ground on each chip appear to provide the *return* (downstream) IO voltage.

Easiest diagnostics to do on the S7s is to play follow the clock. You'll need a scope for that and it's an art rather than a science - sometimes, trouble later on down the chain will disrupt the startup of the first chip, so nothing is seen consistently anywhere.

No detection but I2C works - shows as 48 ASICs and shows 'timeouts' on the syslog page. Temps are shown. CAN sometimes mine in this situation but be careful - the section of the chain that is not getting results back seems to overheat (I guess it only gets fed a new block to work on when the rest of the string does and busy-waits till then)

Nothing at all - no I2C so can't detect a board is there

If someone would like to donate a S9 control board and a dead S9 board, I'll have a look, but I can't afford to do anything which costs money right now.

Good luck!

Cheers,

Allan.

The chips are laid out in banks of three and there are two heartbeat signals one going beginning to end, the other end to beginning. Its actually pretty easy to chase down the problem with a decent multimeter and some patience. You can home in on the bank of chips that is having the problem and then do some resistance and other tests to further pinpoint the issue. The s9 is VERY similar in its layout and troubleshooting can be done in much the same way using the diagnostic points that are located all over the board. Just be VERY careful not to short a test point to a heatsink or you can kill the whole board rather easily.

Thanks guys.

So based on my screenshots, there's no obvious quick fix hey?

No, there never is. If you do all the basic troubleshooting and cant get it back you are basically out of luck.

Heh. I sense the voice of experience.

The other thing which is obvious, depending on your environment, is remove the boards and have a look. I have one board that is unusable - it looks like somehow moisture got in at the fan entry side (possibly a very quickly deceased large bug) and rotted half of the tracks around the "middle" of the chain. If I baby the voltages and speeds, I can get half that board working - but it certainly isn't a DIY effort.

These are tiny chips and pretty much every connection needs to work for the board as a whole to work. Send it to a repair shop and you'll have a far more consistent experience than probing with a multimeter (not that I'm saying that Fanatic isn't right - it absolutely is possible to diagnose if you have the time and no perceived value to the boards)

Need some advice, should I ship the two whole antminer S9's back to Bitmain for warranty repair (one dead board each)? Or, should I try to ship just the dead hashboards to BitmainWarranty.com and pay them to repair?

I'm losing revenue if I ship to Bitmain, but the work should be covered on warranty...

I opted for the Bitmainwarranty Denver site, but please realize that this would invalidate Bitmain's original warranty.
I got a rather stern note from Bitmain afterwards saying that my warranty is kaput, but i did not care too much as it was with earlier S9 batches and warranty was measly 90days back then. Needless to say, people had varied opinions about sending boards back to China. Denver had a quick turnaround time back then, maybe not as quick anymore, but experiences vary. One thing is that bitmainwarranty would also need the whole miner back. This is the way they want it nowadays as far as I know (with autotuned miners).

Wait, bitmainwarranty does not do warranty work????

I've been playing with the S7's for a bit, swapping the voltage regulators and the chips themselves is not too hard; there's a diode that can also fail on there as well. I'd be willing to look at a dead S9, and report the results. But for the most part I've been thinking as long as they are under warranty it wouldn't make much sense to do repairs that could void said warranty.

Hm....

Good day my friend,

I always have the same problem if my ASIC stops for some period of time due to lack of electricity.

Luckily I found solution for my S9 and T9 machines!!!

During start of ASIC you will need to blow with a heated fan(like your girlfrend uses for dry hair after shover) or industrial one.

You need to heat hasging boards while it starts and passes all tets. Normal working temperature of the boards is 40 degres Celcius  so they just don't receive enought temperature to check all chain.

I''m not a specialist and do not know why it works ;D.

Good luck maybe it will help you too.

Believe it or not, I stumbled on the same solution while helping Ognasty get an R4 running. Warm up the air and boards going into it, then fire with power. Once it is hashing never shut it down.

This probably is rooted in a particular chip that has microfractures in the solder joint to the board. Titans would sometimes do this, to fix it permantly I would heat the board up on the preheater without the sink, then use Kestrel flux and air to reheat the chips, then put back together.

If anyone wants to send me a dead S9 board or two I can give this a try.

C

I thought I seen something from Bitmain they did indeed opened a west coast warranty shop. If not I have used the Denver repair and they got my board back working.

I am wondering if the OP tried to plug in the bad board to another controller slot and see if it makes a difference?

I have dealt with this one many times.  for some reason the fix i have found is:

unplug PSU and disconnect ALL power leads.  let it sit fr a few minutes.  hook it all up again and wait for the full boot.  so far 100% sucess w this.  and always its related to power interruption.

If you're able to remove the boards, can't they just be replaced with new ones?  Does anyone sell them?  Are they super expensive?  I'm looking into buying a couple of S9's, but all of the problems I keep reading about scare me.  Not to mention the complaints that Bitmain is horrible at customer service.

Bitmain does not sell replacement hash boards. You can always buy an extra miner and use it for parts!

Bitmain has gone very far downhill and there's no easy way to get replacement boards, especially for the S9. You might be able to find them on the forums, possibly from Aliexpress/Alibaba or eBay/other third party sellers. They are indeed plagued by issues like quality and customer service, I would recommend considering a Canaan A7 over the Antminers. Even though they're cheaper it's not worth the risk of hardware problems and costly repairs imho.

How many hash boards are in each S9?

I'm looking at the Canaan A7's as well.  Why are you saying the S9's are cheaper though?  Bitmain has the S9's at $1415 plus $105 for power supply and Canaan has the AvalonMiner 741 at $798 plus $260 for power supply on Amazon plus the price of a controller.  I also thought that I read the power consumption on the AvalonMiner 741 was way too high.

Most likely an issue with the power side of the board or a bad solder joint. I have no experience with these boards just electronics in general.

Got a dead hashboard on a S9 here as well... Posting a shot in case someone has a diagnostic for what is shows. Occured after a cold boot, was working fine before the shutdown.
https://i.imgur.com/pWtk1E0.png
Any help is welcome!

Let it run till it gets hot then try a restart. Sometimes the boards flunk while cold, indicitive on bad solder joints between board and chip.