Antminer S3 Only Running at 400 GH/s Max?

[NoahWL1]

Hi!  I recently purchased a used Antminer S3 from eBay, never overclocked, run in a clean environment.  I've been running it for a few days now and I've noticed that the readings are always just around 400 GH/s on average, which seems to be a bit too little for me.  On Bitmain's website, they say it runs at 441 GH/s +-5%, which still should leave me with about 420 GH/s at the very least.  I am running at a clock speed of the default 218, all chips are working according to the web interface.  Temperatures never go over 37 degrees.  Am I doing something wrong, or did I just get a bad miner?  Is there anything I can do to increase the hashrate?  I cannot overclock, as my PSU only has 2 PCI-e connectors.  Thanks.

[Zich]

Hi!  I recently purchased a used Antminer S3 from eBay, never overclocked, run in a clean environment.  I've been running it for a few days now and I've noticed that the readings are always just around 400 GH/s on average, which seems to be a bit too little for me.  On Bitmain's website, they say it runs at 441 GH/s +-5%, which still should leave me with about 420 GH/s at the very least.  I am running at a clock speed of the default 218, all chips are working according to the web interface.  Temperatures never go over 37 degrees.  Am I doing something wrong, or did I just get a bad miner?  Is there anything I can do to increase the hashrate?  I cannot overclock, as my PSU only has 2 PCI-e connectors.  Thanks.

What is your psu brand & type?

[NoahWL1]

I was a bit low on money, so I just picked up a Sentey 625 watt PSU and I'm using that.  I also have a Corsair CX-500 running my overclocked Antminer S1 (I don't have to worry about power costs).  Would that be better?  I was planning on trying later tonight. 

[Zich]

I was a bit low on money, so I just picked up a Sentey 625 watt PSU and I'm using that.  I also have a Corsair CX-500 running my overclocked Antminer S1 (I don't have to worry about power costs).  Would that be better?  I was planning on trying later tonight. 

I hate to say this but that is crap psu dude. Amazon customer review all reporting problem.

[NoahWL1]

Oh, dang.  That's a shame I guess.  I'll switch PSUs over.  I don't care about the S1 as much since it draws more power anyways.  The reason I got it in the first place was because someone else running the same set up as mine had the 725 watt version and was able to run an S3+ and the new R-Box 2.0 off of his, no problems.  Guess I'll just have to deal with what I have and make the best of it.  Thanks for your help.

[Zich]

Oh, dang.  That's a shame I guess.  I'll switch PSUs over.  I don't care about the S1 as much since it draws more power anyways.  The reason I got it in the first place was because someone else running the same set up as mine had the 725 watt version and was able to run an S3+ and the new R-Box 2.0 off of his, no problems.  Guess I'll just have to deal with what I have and make the best of it.  Thanks for your help.

No problem dude 
Let see how is the performance after changing better psu.

[NoahWL1]

Switched out the PSUs and the S3 only ran at something like 13 GH/s.  At least that's what it said in the average.  It had solved 60 but rejected 500 in the few seconds I had to open the interface.  Let it run for another few minutes, no change.  I just figured it didn't have enough power even though it should; 450 watts on the 12 volt rail and the S3 only takes 355.  Oh well.  I switched back the PSUs and... worse?  .19 GH/s... Fantastic... Letting it cool down for 10 minutes, that always seems to fix any problems I have.  I'll see how it does from there.  Hopefully I didn't damage it, I don't see how I could have.

[NoahWL1]

Although the S1 ran fine on the Sentey PSU.  No problems at all.  Same as the Corsair I had been using for months.

[NoahWL1]

Reset the S3 to factory defaults.  Seems to have fixed that problem.  I'll let it run for a day to get another average to make sure and then try to switch the PSU again.

[MyRig]

 for the bitcoin Miner, please select 80 Plus gold or plat. Little investment into the PSU makes a bit difference in a long run

Reset the S3 to factory defaults.  Seems to have fixed that problem.  I'll let it run for a day to get another average to make sure and then try to switch the PSU again.

[NoahWL1]

Yeah, I've noticed :/  Not a good PSU.  It's only running at 366 GH/s now.  Thanks for the info.