Topic: [GUIDE] Undervolt antminer s1 [1.19W/GH at the wall] - page 7. (Read 69365 times)

^that does happen. Its something that happens as the lead 'cures' and becomes less resistive as it does. Same thing hapened pencil-modding bitfury units - after a day or so from modding it would become unstable due to higher voltage.

IME: after ~6hrs the 'curing' is about half-complete, at 12hrs about 75%, at 2days you should be totally stable and not see it stray any further. Its worth keeping this in mind when modding, particularly if the unit becomes less stable after a day or so from when it was modded

I undervolted my S1 V1.3 from year 2013 (very thin metal frame) with 3.3k resistors. Voltage is 0,82 and I´m hashing now with 250mhz and 125GH 2% error rate in very warm room. Measurement point was different than in first page picture, I measured from top of low row of capacitors.
I was shure first that operation was succesful but patient died as miner didn't work with 193 or 200mhz

Power consumption 170VA from wall.

You know, I'm starting to suspect BTCGuild's Active worker summary.  If I look at the S1's self reported Miner status, it's reporting 127.5GH.  But nearly every time I look at BTCGuild it says >130.  I'd say it's about 132 +/-4.  However, if I look at BTCGuild's hourly chart, the numbers are definitely averaging less than 130GH.  Also, my S3's are kinda doing the same thing.  Reporting higher on BTCGuild than the local Miner Status.

So, 127.5GH @151W is more like 1.19 W/GH.  I'm kinda surprised they're doing even that well, as I still get HW errors...Running about 11-12K per 58K accepted shares.

heck that is better then my freq 275 hash 140gh and 187 watts

I wanted to post my thanks for this.  I have 2xS1 that I may have gone a little heavy on the pencil, as they wouldn't mine stably @275mhz.  I even checked the voltage and they were all spot on .84v to .86v.  However, I clocked them on down to 250Mhz and they hash great @130GH.  And on a gold rated PSU the two combined are only pulling 303W @ the wall.  So, I'm considering 1.16 W/GH a success!

Thanks again!

Or watch my video guide

how do i check the voltage?  also on this particular S1 the yellow voltage deals are super tiny compared to my other S1, would that make a diff?

I figured it out, for some reason even though I dropped each resistor to 2.8-3k with my pencil they all were somehow even lower down to 2.5k after a few days, i wonder if the lead can heat up and do something weird which would lower the resistance even further?

  you would hash at 140 gh and use 280 watts.


you need to understand how easy it really is to do.  2 -4 lite to medium pencil strokes on 8 resistors 4 on each side of the miner.

watts will drop from about 280 to about 170-200 depending on how perfect you got your resistors to drop.

So what would happen if I just underclock to 275 without doing the pencil mod.

For 275 your voltage should be up around 900mv.
What is your voltage?

so I undervolted 1 of my S1's to 275 freq and using pencil got each resistor down under 3 (some 2.8 some 2.9)

its been a couple days and im averaging 118GH on the ant GUI

that seems low doesn't it?

both units are on a 660w seasonic platinum PSU drawing 560 watts between the 2 (one S1 is overclocked to 200GH)

only thing I can think of is I ran out of PCIE cables to power my new S3's so I pulled one from the S1 and rigged one blade on the undervolted S1 with molex to PCIE adapter (using 2 molex perif cables coming from the PSU so the adapter is not on 1 cable but 2)  I figured this would be ok considering the S1 is undervolted and drawing less power

  Good thing I did the soldering part before drink #6.  Brought back many memories of modding PS2's back in the day.    ...good times.

  Software part was what messed me up.  I couldn't login with putty after so long b/c the miner shut down or wasn't available.  I panicked, thought I destroyed it = drunken, ranting post.  Plus my batch 1 S3's still haven't shipped.  

Can someone post a link or give info as to what the fields in LuCI mean?

  From what I gather reading this thread, "HW" is errors.  How are you guys calculating error %?   I'd like to tweak it a bit for the best result...I soldered pot's in and adjusted each bank to 0.847V - 0.853V.  Each Asic bank seems to have a balanced voltage output to maybe 4 Asics each(8 in the bank).   I took readings from the capacitors(referred to as "yellow thingy" in this thread) and the capacitor below it.(they are polarized and I read from the side with the bar on it, it should be the + side of the Cap).  Also, is there a way to restore the factory firmware?  I may have drunkenly f00ked it with putty.

  This machine is messed up from the start.  It had HW problems before the mod compared to the 2 newer S1's I have.  Also, my load hasn't changed much.  The board is stamped with build date 2013/12/16.

Currently seeing:
11h2m uptime
139.xx GH/s avg.
14,562 HW.
Load 2.30 2.15 2.14.
All asics showing good(0's, not x's).

Kill-o-watt readings:
Amperage: 1.46A
Wattage: 170W

  It's a lot better than the 3.3A @ stock 180 GH/s!!!

  On a sidenote, I'd like to offer my sincere apologies for the Steve Jobs comment.  I realize that some idolize him and think that he was great for technology(electronics).  As a degreed tech guy, I see him as just a great marketer and the reason we have micro-transactions aka nickel and diming for everything nowadays.  There is one thing we can all agree on...  Steve Wozniak is a genius!!  :cheers

Thank you for the help! turns out the red and black leads was pretty specific. underclocked and undervolted, ~125gh/s at 170 watts. 250mhz.

Ya that actually took me a little while to figure out too. Had to look up an SSH tutorial just to figure out what to do. When you press I you are in edit mode, and you can type and delete and whatnot but nothing saves. To exit edit mode, just press ESC.  Now you type in :wq to save the file you just edited, and reboot the miner.

Also gotta watch out for the SSHing and drinking   From my experience electronics and drink don't mix well!

Sorry, too much drinkin...

I'm following mstrongbow's post above.  I can get to the edit part and enter the code for 275M...copy & paste does not work.  I have to enter all commands manually.  After I enter the info, I press "I" and it just enters "I" into the file.  I can't get out of the edit portion to do the ":wq" command.

The miner boots and runs for a few minutes but starts beeping b/c of all HW(errors I think) and shows no GH/s.

Tried again and seems to be working now.  Putty is a PITA to navigate through.  I watched the video but the guy was on a mac and it was different.

ok dude calm down and stop thanking god that steve jobs is dead, i mean after reading his book im pretty sure he was quite an awesome guy. Second of all, instead of throwing your tits ariund, why you no tell us whats aactually wrong?

Just did a schweet hardware mod but f'd up the software stuff.  Bad things with Putty.  Think I deleted some stuff.  

Great Job, it works! Thanks guys!
And I learned to like linux, nice. A bit like the good old DOS-times. 

Now I can try the 0.75V mod. Once I get my homepage/photobucket working I will share some results.

Happy mining! BTCBTCBTC

1) its a hexcode that the chips interpret as a frequency command/modifier. There are formulas available to calculate a value, but plenty shared in the forums for common MHz intervals.
2) this is the value that the miner displays. as far as i know you could type words in that spot and still mine at whatever the hexcode frequency is
3) timeout is the expiry of hashing a specific nonce i think

ps: '#' in coding denotes that what is after it is a text comment in the file but not a program command, usually used:        function /file   #this does yadda