[GUIDE] Undervolt antminer s1 [1.19W/GH at the wall]

[navigator]

I recently put 4 undervolted S1's on a single CX750 using decent looking 18ga pcie splitters. Each one running 225mhz, 115gh, ~137w for a total of 460gh/550w. The wires don't even get warm. The PSU is a lil warm. Thinking about bumping them up to 140gh/~166w when I get time. Just ordered some more splitters so I can do 4 more on another CX750.

Here are the splitters I'm using:
http://www.ebay.com/itm/131197541426

I've noticed that the S1's that performed well at 200gh with low hwe are the ones hardest to undervolt. Some of them eventually show up X's,etc... And the S1's that didn't perform well overclocked are the ones easiest to undervolt. I have one S1 that would never go above 195gh without many hwe. Now its been running for 78hrs at 115gh and only 3 hwe. Yes just 3.

[bitcoin_miner]

many thanks for this guide https://bitcointalk.org/index.php?topic=526060.0
I use Multiturn potensio for undervolt. https://bitcointalk.org/index.php?topic=526060.msg7586392#msg7586392

SSH I follow : https://bitcointalk.org/index.php?topic=526060.msg7828393#msg7828393
I choose Freq (275 MHz):
option 'freq_value'    '0A81'  #275M
option 'chip_freq'     '275'
option 'timeout'       '45'

before undervolt : 454W from wall
after undervolt : 222W from wall

this is result Ghs my S1 antminer.

[gentacomp]

Any guide for S3 ?

[Bitcoin++]

I'd like to minimize W/GH.

So far I've only tried OP's recommendation. My miners ended up at 185W @ 140 GH = 1.3 W/GH.

Has anyone underclocked even more, and what W/GH do you reach?

EDIT : See OP. He uses 0.85V but shows that 0,75V should be even more efficient. For 0.85V the resistance shall be between ~2.8kOhms and ~3kOhms. We should find out what Ohm that suits the 0.75V setting

I have 9 penciled mod down and was thinking of trying to go lower in a couple of weeks. Let me know how it works for you.

I tried resistance between ~2.3kOhms and ~2.6kOhms. Both my Ants run stable at around 128 GH with HW error well below 1%.
New score is 150W @ 128 GH = 1.17 W/GH

I use
#option 'freq_value'    '0981'  #250M
        #option 'chip_freq'      '250'        
        #option 'timeout'         '56'  

I suggest you try this first. If HW error is very low you can try at a higher frequency. If the HW error is high (>1%) you can try a lower frequency. List of frequency settings is in this thread.

EDIT: A bonus is silence. Fans run at only 1320 RPM, hardly noticeable, and to eliminate any vibrations I put foam under the miners.

[bitcoin_miner]

After 4 days run in undervoltage, my antminer S1 stop hashing.. this is screenchoot antminer :
anyone here suggest me to repair it?

many thanks for this guide https://bitcointalk.org/index.php?topic=526060.0
I use Multiturn potensio for undervolt. https://bitcointalk.org/index.php?topic=526060.msg7586392#msg7586392

SSH I follow : https://bitcointalk.org/index.php?topic=526060.msg7828393#msg7828393
I choose Freq (275 MHz):
option 'freq_value'    '0A81'  #275M
option 'chip_freq'     '275'
option 'timeout'       '45'

before undervolt : 454W from wall
after undervolt : 222W from wall

this is result Ghs my S1 antminer.

[bitcoin_miner]

Now my antminer S1 ran again.
trouble caused in previous I use VR multitune 100K, several VRs shift value below 2.8K.
After I replace with 10K Multitune and set to 2.85K. My S1 work..

After 4 days run in undervoltage, my antminer S1 stop hashing.. this is screenchoot antminer :
anyone here suggest me to repair it?

many thanks for this guide https://bitcointalk.org/index.php?topic=526060.0
I use Multiturn potensio for undervolt. https://bitcointalk.org/index.php?topic=526060.msg7586392#msg7586392

SSH I follow : https://bitcointalk.org/index.php?topic=526060.msg7828393#msg7828393
I choose Freq (275 MHz):
option 'freq_value'    '0A81'  #275M
option 'chip_freq'     '275'
option 'timeout'       '45'

before undervolt : 454W from wall
after undervolt : 222W from wall

this is result Ghs my S1 antminer.

[bitcoin_miner]

can S1 undervoltage make profit?
caused now 140GH/s make $1.5/day 

[philipma1957]

can S1 undervoltage make profit?
caused now 140GH/s make $1.5/day 

all depends on you power cost. at 15 cents a kwatt and burning 185 watts for 140 gh it pays above the power cost.

  the power cost is around 67 cents a day

for 15 cents a kwatt.   


so 1.50 - .67 = 83 cents a day profit.

do not forget that in 50 days or so it will be a helpful little heater

[squashpile]

246W @275 averaging around 141GH/s. Isn't that wattage high? THat's messed up. I need to redo it.

[mxz280]

179W @275 averaging around 140GH/s.

[mxz280]

179W @275 averaging around 140GH/s.

0.85V
Elapsed
18d 18h 25m 40s
148.15GH/S(5s)   
140.10GH/S(avg)   
402,578Accepted   
74,727,110HW   
1,957WU
52,743,027DiffA   
98,046DiffR   DiffS   
182,950,239BestShare

[aurel57]

246W @275 averaging around 141GH/s. Isn't that wattage high? THat's messed up. I need to redo it.

I have 9 S1's running all at 275 MHz. My watts at the wall went from @375 watts to 170 watts and they hash at 135-140GHs. I pay .125 per KW, so I spend @.51 per day on electric with the miner making @$1.50 a day at today's difficulty and BTC value.

[MrTeal]

I did a couple today just as a test as it's now at about the crossover point where profitability is the same underclocked as overclocked. I soldered a 8.75k in parallel with R3 to bring it down to 0.85V, and changed the fan for a Helix 120mm since I have a pile of them from my H220s.

Between two units I dropped from 843W at the wall (on an off brand 850W supply) and ~405GH/s to 341W and 281GH/s. They're super quiet as well, though I'm not yet convinced that with low enough ambient you couldn't just run them without a fan.

[catoboli]

This was super helpful, i can't believe how quickly diff is going up, crazy. i feel like my s3's are going to be obsolete next week.

[catoboli]

i currently have 6 s1's running at 200gh/s at 400w each powered by 2 corsair AX1200i's and its getting to the point where I'm not making much, i probably won't make anything after this next jump in diff unless BTC goes back up to 600.

Im looking to get these guys down to 200w each, and get all 6 on 1 psu.

What appears to be the best config for them running around 200w? the Corsairs are a beast and although rated at 1200 I've run some of them at 1300 and 1400 for an extended period of time with no issues. I had to put the AX1500i that i have my 4 overlocked S3s connected to on its own circuit breaker. but then again at the price they are they should be crazy good pus's

i want to drop the voltage down to .85. it looks like some people had some good luck getting around 150-160 ghs here. what freq are people using in this area.

and i haven't seen much talk of dropping the voltage down to .75 what kind of results are people getting there.

[moug]

I found the best way is to have the cat5 un plugged, then pencil the resistors until the voltage reads 0.85 volts. Blow off the pencil dust.
Lay the unit on it's side so it's easy to work on. Get some 2.5 or 3.5 reading glasses or greater.

After both sides done then plug the cat5 back in and SSH the unit and set it to 250 and record to GH/s for 1/2 hour then set to 275 and record for 1/2 hour then set to 300 and record.
Some units work better at 250 and some at 275, recheck the voltage and adjust. I got around 160-170 watts and 120-140 GH/s on 12 units. GHash is good place to test if you already mine there.

[aurel57]

i currently have 6 s1's running at 200gh/s at 400w each powered by 2 corsair AX1200i's and its getting to the point where I'm not making much, i probably won't make anything after this next jump in diff unless BTC goes back up to 600.

Im looking to get these guys down to 200w each, and get all 6 on 1 psu.

What appears to be the best config for them running around 200w? the Corsairs are a beast and although rated at 1200 I've run some of them at 1300 and 1400 for an extended period of time with no issues. I had to put the AX1500i that i have my 4 overlocked S3s connected to on its own circuit breaker. but then again at the price they are they should be crazy good pus's

i want to drop the voltage down to .85. it looks like some people had some good luck getting around 150-160 ghs here. what freq are people using in this area.

and i haven't seen much talk of dropping the voltage down to .75 what kind of results are people getting there.

I am thinking in about 30 days or so I will try and drop mine down lower unless the value of BTC goes back up that is.

[eoakland]

Hi i want to give a big thank you to the OP of this thread for his step by step tutorial and for his hard work in providing an extended lifespan to the beast of it's time the s1.  with that said, i was wondering if OP is currently mapping out the s3 and looking into the possibility of this being done also (when difficulty catches up to earning potential) ?

 

[eoakland]

I did a couple today just as a test as it's now at about the crossover point where profitability is the same underclocked as overclocked. I soldered a 8.75k in parallel with R3 to bring it down to 0.85V, and changed the fan for a Helix 120mm since I have a pile of them from my H220s.

Between two units I dropped from 843W at the wall (on an off brand 850W supply) and ~405GH/s to 341W and 281GH/s. They're super quiet as well, though I'm not yet convinced that with low enough ambient you couldn't just run them without a fan.

that is pretty bad ass right ?  the first thing i noticed was the noise level reduction on the s1.  before my living room sounded like it had a mini-jet taking off, now it's very silent and does not produce as much heat.  i am tempted to buy those goofy little heatsinks for the chips, but i know it probably is not required.  so i don't think i will be dumping anymore $ into the s1. 

mr. teal, you may know better, but is it possible to daisy chain the s1's ?  say if someone has a antminer with a bad controller card, can you splice it into an antminer that has a good controller card and have both units run from it ?    thanks

[aurel57]

I did a couple today just as a test as it's now at about the crossover point where profitability is the same underclocked as overclocked. I soldered a 8.75k in parallel with R3 to bring it down to 0.85V, and changed the fan for a Helix 120mm since I have a pile of them from my H220s.

Between two units I dropped from 843W at the wall (on an off brand 850W supply) and ~405GH/s to 341W and 281GH/s. They're super quiet as well, though I'm not yet convinced that with low enough ambient you couldn't just run them without a fan.

that is pretty bad ass right ?  the first thing i noticed was the noise level reduction on the s1.  before my living room sounded like it had a mini-jet taking off, now it's very silent and does not produce as much heat.  i am tempted to buy those goofy little heatsinks for the chips, but i know it probably is not required.  so i don't think i will be dumping anymore $ into the s1. 

mr. teal, you may know better, but is it possible to daisy chain the s1's ?  say if someone has a antminer with a bad controller card, can you splice it into an antminer that has a good controller card and have both units run from it ?    thanks

Once the S1 upgrade kits get out we should see people figuring out how to run a lot of boards with one controller.