Capacitor repair on an Antminer S1 board?

[cloverme]

I got a new S1 from bitmain but a component is missing from one of the blades. I contacted them, but they don't seem to understand what the situation is as they're telling me to press down on the chips and to recycle the power.

A little bit of research on my own has revealed that one of the capacitors has broken off the board. The identical capacitor is right next to it, I could probably repair it myself, but having some trouble identifying the capacitor.



Any help in ID'ing the capacitor or you know someone that repairs Antminer S1's in the states would be appreciated.

Thanks

[wpgdeez]

Heres what you don't want your cap to look like ...

[TheRealSteve]

It's a 1500 micro Farad  (µF), 2.5V rated, Organic Conductive Polymer, SMD package, capacitor.  The 'C4' at the top is just a date code.  Looks like it's for power - you could probably get away with a different one.  However, this is really something Bitmain should be fixing - either by having you RMA it, or, in agreement, sending you a spare part with the understanding that you'd be voiding your warranty.

[cloverme]

It's a 1500 micro Farad  (µF), 2.5V rated, Organic Conductive Polymer, SMD package, capacitor.  The 'C4' at the top is just a date code.  Looks like it's for power - you could probably get away with a different one.  However, this is really something Bitmain should be fixing - either by having you RMA it, or, in agreement, sending you a spare part with the understanding that you'd be voiding your warranty.

Thanks, agreed. I've tried contacting Bitmain about an RMA (included the photo), but they don't seem to understand what I'm trying to communicate. I'll keep trying.

[TheRealSteve]

Thanks, agreed. I've tried contacting Bitmain about an RMA (included the photo), but they don't seem to understand what I'm trying to communicate. I'll keep trying.

Hah.. it's.. pretty obvious from the photo what the problem is.  Note that I have no idea how crucial that component is in their topology, but either which way they should be able to tell you what to do.  I wonder if that cap was rolling around somewhere in the box you received.. seems more like something knocked it right off

[cloverme]

No doubt, I looked in the ESD bag and the box and no dice... It does hash, but 30% of the chips are shut down.  My guess is that it happened before someone put it inside an esd bag.

[GigaWave]

Any luck with Bitmain helping you?  I had one explode, looks like wpgdeez'z below. Except it was the cap under the 12V+ header.(One farthest left in the below picture)  Funny thing to is, it was the same side of the miner. IE, the side opposite the control board.

Still haven't found the cap cover. Sure did give off a nice spray of sparks.

Heres what you don't want your cap to look like ...

[uhoh]

Should be a straight forward job. Should be able to find this in pretty much any electronics store. Though if they're popping this easily, might be better to replace them all with 5V caps.

[wpgdeez]

Any luck with Bitmain helping you?  I had one explode, looks like wpgdeez'z below. Except it was the cap under the 12V+ header.(One farthest left in the below picture)  Funny thing to is, it was the same side of the miner. IE, the side opposite the control board.

Still haven't found the cap cover. Sure did give off a nice spray of sparks.

Heres what you don't want your cap to look like ...

They gave me an RMA number for their account with UPS and UPS didn't know what I was talking about. I haven't bothered fixing it, maybe i'll get someone to solder on a new cap and see if it will hash again. Not sure what caused the CAP to pop, I would think some other underlying issue.

[uhoh]

Any luck with Bitmain helping you?  I had one explode, looks like wpgdeez'z below. Except it was the cap under the 12V+ header.(One farthest left in the below picture)  Funny thing to is, it was the same side of the miner. IE, the side opposite the control board.

Still haven't found the cap cover. Sure did give off a nice spray of sparks.

Heres what you don't want your cap to look like ...

They gave me an RMA number for their account with UPS and UPS didn't know what I was talking about. I haven't bothered fixing it, maybe i'll get someone to solder on a new cap and see if it will hash again. Not sure what caused the CAP to pop, I would think some other underlying issue.

It'll probably be a pretty cheap cap that's being run too close to rating. Any TV repair shop will be able to fix this for you, the traces are intact, should take them a few seconds and cost virtually nothing. Better still though, if there is not many of them, have them all changed for a higher voltage replacement.

EDIT: If you get a replacement yourself, make sure its marked 'Low-ESR'.

[Airwhale]

I've repaired two antminers with caps that broke,  one due to an accadent when moving an S1,  the other due to a return from shipping damage when I ebayed the miner.  It's a really easy repair. I agree that bitmain should probably just issue a refund/ ship you another blade. But, If you take the antminer to any good electronics store,  they should be able to walk you through the steps.  Or if you are in the San Francisco Bay area,  shoot me a PM and I'll do it for you over the weekend. =)

While you are figuring this out,  btw,  there is no reason not to have to other blade plugged in and earning for you.  

[GigaWave]

Any luck with Bitmain helping you?  I had one explode, looks like wpgdeez'z below. Except it was the cap under the 12V+ header.(One farthest left in the below picture)  Funny thing to is, it was the same side of the miner. IE, the side opposite the control board.

Still haven't found the cap cover. Sure did give off a nice spray of sparks.

Heres what you don't want your cap to look like ...

They gave me an RMA number for their account with UPS and UPS didn't know what I was talking about. I haven't bothered fixing it, maybe i'll get someone to solder on a new cap and see if it will hash again. Not sure what caused the CAP to pop, I would think some other underlying issue.

Yeah, I would like to know more about them. As in exactly what they are doing.

In my case I had a power outage and the PSU did not come back on. Unplugged and replugged the mains power about 3-4 times within about 15 seconds trying to get it to power back up. On the final try the cap popped. I removed power from the one blade and everything powered up fine.  Still no idea what the issue was.

[klondike_bar]

the S1 will run fine without that capacitor, but you may need to treat it special in order to get it to power up okay.

1) power up unit normally.
2) if there are a few non-working chips (there likely will be), reboot the miner but leave the PSU on
3) the miner will reboot and the power will be stable enough in other capacitors that all the chips read up fine.

I have a unit missing that cap (i found it in the box after) and its running fine stock without doing any repairs just using the above method

[edgar]

i also have recently received and S2 with broken & missing caps.

had exactly the same struggle trying to get bitmain to comprehend the situation.

dozens of messages relayed and he almost always says , try it again, reseat it, off & on, try again, dont worry - try again.


i have already seen images of exploded caps and the resultant non assistance.


as it happens my rig is running 9 0f 10 blades seemingly fine but it will live its life outside, im not risking my wooden house catching on fire so bitmain can save 0.01 dorrar worth of caps & 2 dorrars worth of thermal paste....


Disgusted.! 


but hey....moar coupons....ffs!!

[togame]

I recently received an S1 which is missing a cap from every pair. It looks like they were just never there. I still haven't heard back from bitmain yet. Does anyone know where we can purchase replacements? As close to these as possible is preferred.

https://i.imgur.com/lj274W7l.jpg

[faetos]

I didn't pack one well when I moved and broke two of those off one board. It's been running well for over two months now. I don't OC it and haven't seen any adverse effects from the two missing parts.

[intron]

I recently received an S1 which is missing a cap from every pair. It looks like they were just never there. I still haven't heard back from bitmain yet. Does anyone know where we can purchase replacements? As close to these as possible is preferred.

https://i.imgur.com/lj274W7l.jpg

It is very well possible these were 'NOPOPs',
parts that were not ment to be populated
on the board.

Sometimes after testing a design, it turns
out some parts can be omitted without
decreasing the performance of the circuit.
Parts are then not placed during production
in order to save a few bucks.

When the solder on the pads looks nice and
regular, there were never caps on that location.

[togame]

I recently received an S1 which is missing a cap from every pair. It looks like they were just never there. I still haven't heard back from bitmain yet. Does anyone know where we can purchase replacements? As close to these as possible is preferred.

https://i.imgur.com/lj274W7l.jpg

It is very well possible these were 'NOPOPs',
parts that were not ment to be populated
on the board.

Sometimes after testing a design, it turns
out some parts can be omitted without
decreasing the performance of the circuit.
Parts are then not placed during production
in order to save a few bucks.

When the solder on the pads looks nice and
regular, there were never caps on that location.

I understand that, however this unit does not perform as intended, which is why I contacted bitmain. This unit runs quite well for a few hours then performance decreases to a seemingly arbitrary rate. I've had it perform anywhere from 9 to around 140 Gh/s. The only way for me to fix this is to cycle the power.

[edgar]

I recently received an S1 which is missing a cap from every pair. It looks like they were just never there. I still haven't heard back from bitmain yet. Does anyone know where we can purchase replacements? As close to these as possible is preferred.

https://i.imgur.com/lj274W7l.jpg

It is very well possible these were 'NOPOPs',
parts that were not ment to be populated
on the board.

Sometimes after testing a design, it turns
out some parts can be omitted without
decreasing the performance of the circuit.
Parts are then not placed during production
in order to save a few bucks.

When the solder on the pads looks nice and
regular, there were never caps on that location.

I understand that, however this unit does not perform as intended, which is why I contacted bitmain. This unit runs quite well for a few hours then performance decreases to a seemingly arbitrary rate. I've had it perform anywhere from 9 to around 140 Gh/s. The only way for me to fix this is to cycle the power.

yea but.... think how many whole cents Bitmain saved.

doesnt it seem worth it now?

Even with all components in place & functioning correctly, i imagine the thermal paste under your s1 blades could well be retarded/ineffective.

IF its even thermal grease...it might just be old engine oil mixed with fake baby milk powder!

Still - waste not, want not!

[jimrome]

I recently received an S1 which is missing a cap from every pair. It looks like they were just never there. I still haven't heard back from bitmain yet. Does anyone know where we can purchase replacements? As close to these as possible is preferred.

https://i.imgur.com/lj274W7l.jpg

It is very well possible these were 'NOPOPs',
parts that were not ment to be populated
on the board.

Sometimes after testing a design, it turns
out some parts can be omitted without
decreasing the performance of the circuit.
Parts are then not placed during production
in order to save a few bucks.

When the solder on the pads looks nice and
regular, there were never caps on that location.

I don't think they should be DNPs, as they're the output caps for the buck regulator (the same part (TPS5335) you used on the Bitfury 25GH boards).

If anyone's interested here's the relevant schematic section.



Edgar: from what I've seen the heatsink compound used is of passable quality - the actual application during assembly varied wildly (too much, too little). The HS screws were also installed erratically, resulting in voids under the heatsink where no or little contact was made. I also had several where cutting/tapping fluid (which hadn't been cleaned out properly) oozed out from the heatsink screw holes and mixed with the compound, resulting in a runny mess.

Don't get me started on the HS design itself..