Overvolting and overclocking Antminer S7

[Pissenlit]

Hello guys,

Is there any of you that are running OC'd S7? I know that some tests have been done on short term, but is there someone who successfully tested it on the long term?

My S7s are already running on 12.7V but at stock frequency. I want to overclock my oldest one to see where it can go, calculate the efficiency at the wall at different frequencies, and let it work as long as it can at high frenquency. Ambient temp is less than 20C in the warehouse and my test miner have 0.0000% error rate, amazing.

 

[philipma1957]

Hello guys,

Is there any of you that are running OC'd S7? I know that some tests have been done on short term, but is there someone who successfully tested it on the long term?

My S7s are already running on 12.7V but at stock frequency. I want to overclock my oldest one to see where it can go, calculate the efficiency at the wall at different frequencies, and let it work as long as it can at high frenquency. Ambient temp is less than 20C in the warehouse and my test miner have 0.0000% error rate, amazing.

 

I did it with the batch 2 and got very good results.

if you have the older gear batch 2 to 7 with 162 chips

set fans at 60% which is about 4200rpm .  the  fans max at 4600 rpm and about 75% setting but my gear did better at the 60% setting.

as long as temps are 62 c and errors are under 0.0010%  you are good to go. 


I don't own any match 8-13 gear  with 145 chips

[Pissenlit]

philipma1957, thank you for your reply. Is your B2 still running at high frequency? For how long?

I only have B8+ S7s. Fans at 80% running 4300rpms, and 60-65C temps.

[philipma1957]

philipma1957, thank you for your reply. Is your B2 still running at high frequency? For how long?

I only have B8+ S7s. Fans at 80% running 4300rpms, and 60-65C temps.

I ran it for 2 months at those speeds    my gear was a batch freq rated 575  over volted at 12.5 volts






looking for the highest one  




 so this is a free 575 batch 2 running at freq 631  just under 5100 errors really good.  this machine can touch .245 watts per gh at the freq of 616 with 0.0001% errors.  by far the best of all 18 or 19 s-7's I have owned

[carlosmnk]

I'm thinking about to overvolt a batch 3, but it have a lot of hw (0.035) with stock freq (600mhz), i wanna try 12.1v, then 12.2v with 600mhz...
When i try to put 612mhz the hashrate is the same, because the hw goes up... i tried up to 625mhz with same results... 
But never tried to overvolt it... 

[Pissenlit]

Try to overvolt it without overclock it. Your error rate should get lower.

[Entropize]

I tried overclocking all of my s7s but only half of them could take it at stock voltage. The overclocked ones are stable at 5TH/s and 5.1TH/s. I just jumped their speed one step at a time until they started getting huge amounts of errors or wouldn't boot correctly then dialed them back. Two batch 11s had completely different results, one couldn't take any notch up and the other pumps out ~5TH/s comfortably. You just have to try it on the individual hardware and see what it can do.

[RadekG]

philipma1957, thank you for your reply. Is your B2 still running at high frequency? For how long?

I only have B8+ S7s. Fans at 80% running 4300rpms, and 60-65C temps.

I have B8 running at 750MHz stable at 5TH/s. Overvolting 12V rail has no influence, voltage is stabilized internally.

[RadekG]

I did it with the batch 2 and got very good results.

if you have the older gear batch 2 to 7 with 162 chips

set fans at 60% which is about 4200rpm .  the  fans max at 4600 rpm and about 75% setting but my gear did better at the 60% setting.

as long as temps are 62 c and errors are under 0.0010%  you are good to go. 


I don't own any match 8-13 gear  with 145 chips

IMO older batches should work well at 12.8V and 700MHz reaching 5.67Ths - chip heatsinks are same dimensions older and newer batch, so OCing older batches to 700MHz must be safe and still better GH/W ratio than older batches

[philipma1957]

I did it with the batch 2 and got very good results.

if you have the older gear batch 2 to 7 with 162 chips

set fans at 60% which is about 4200rpm .  the  fans max at 4600 rpm and about 75% setting but my gear did better at the 60% setting.

as long as temps are 62 c and errors are under 0.0010%  you are good to go. 


I don't own any match 8-13 gear  with 145 chips

IMO older batches should work well at 12.8V and 700MHz reaching 5.67Ths - chip heatsinks are same dimensions older and newer batch, so OCing older batches to 700MHz must be safe and still better GH/W ratio than older batches

I was able to feed 12.5 volts max    and do 631 vs rating of 575  can't complain about that machine

[wmtomlinso]

I curious what kind of lab grade power supply you guys are using that puts out 1300+ watts and will hold the 12V rail to 1/10 of a volt reliably???  that would be a very expensive PSU

That sounds funny - I over volted it to 12.8, like do you think the 12V is actually 12.00000 and doesn't fluctuate?  Any PC or server grade PSU is going to be all over the place, varying from like 11 to 13 V

[Pissenlit]

I'm using IBM 2880W server psus with 2x S7s per psu. Voltage is uber stable. Effiency is better with 1x S7 but it's not a big difference.

[wmtomlinso]

Ah, well that explains it,  that 2880 is a really nice psu.  To purchase one from IBM/Lenovo as part of a blade system, costs over $1000.   Its amazing we can get these server PSU's so cheap. I have one 2880 and i think i paid less than $100, and it was just a backup redundant supply - it was practically new. It a real workhorse too.

[philipma1957]

Ah, well that explains it,  that 2880 is a really nice psu.  To purchase one from IBM/Lenovo as part of a blade system, costs over $1000.   Its amazing we can get these server PSU's so cheap. I have one 2880 and i think i paid less than $100, and it was just a backup redundant supply - it was practically new. It a real workhorse too.

The 2980 is better then the 2880 uses the same breakout board.