S3+ (BM1382) Overclocking with voltage setting

[adaseb]

Still running some tests. Decided to overclock from 250M to 275M and see what happens. Changing the voltage parameter also but resulted in no changes.


Remember how some voltage readings were over >0.8Volts in my previous post. Well at 275M those voltages go back to the average values.

VDD4=0.824V went to 0.777V
VDD7=0.824V went to 0.777V


-------------------------------------------------------------------------
No idea what is going on.

[tokingtoking]

Mine 250M at 0720.
Average 501gh/s

Is it normal?

[Mikestang]

Great thread, just what I was looking for.  Marking it to save to read for later, have my first S3+ showing up soon.  Thanks.

[cflocation]

Are these stable when overclocking. Have any of you noticed any failures at all?

[Mikestang]

Fantastic post and great information, thank you so much!  Looking forward to squeezing a little more out of my S3+.

It has been suggested that the voltage setting under the Miner Configuration -> Advanced Settings tab that is in the new S3+ firmware is a left over from the S4 firmware and is of no effect to the S3+, however this is not the case. While trying to figure out the effect the setting had, I changed one of my slightly OC'ed S3's voltage setting to 0850 and left it there for as it seemed to slightly improve the speed it was hashing at. This unit (like the rest of my S3's) was powered by a 550W server PSU, and having left the unit to run for weeks, the PSU started restarting every so often, which none of the others ever did. I finally realised that the PSU was dead and the only difference in settings was the voltage, which confirmed to me that the setting surely has an effect on the S3+, thus this post.

I looked up the datasheet for the BM1382 chip that is used in the S3+ and found 2 sections that helped me work out what caused the fauilre of my PSU (and also led me to properly use the voltage setting to properly overclock an S3+).

1. The typical hash rate and power table



2. The input timing for the chip



The initial table has voltage settings and hash rates at each voltage, while the second table has the hash rates and frequencies to achieve them. Putting these together, I came up with the following.



I have added an extra row for each voltage setting of 0.75v and 0.80v as I found that with the two units I overclocked they had a higher HW error % at the frequencies in the datasheet. When I upped the frequency a notch, the HW error % reduced to acceptable levels. It goes without saying that you may need to add the added frequencies as they are not in the shipped firmware, here's alink to how you can add them: https://bitcointalk.org/index.php?topic=699064.msg8370071#msg8370071

Also worthy of note is that setting a chip voltage to 0.85 results in a (datasheet / theoretical) wattage draw for the S3 (32 chips) of 544 watts. Remember the server PSU that I was using on the over-volted S3 that I mentioned earlier was rated at 550 watts ..... no wonder it gave up its ghost! So ensure you have an adequate PSU powering your S3 before you begin. Addidtionally, it may be worth noting that a fully populated 6 pin PCI-e connector will carry a maximum of 24 Amps @ 12V = 288 Watts (though I normally assume they can only carry 22.5 Amps @ 12V = 270 Watts), so you may need to power your S3 with all 4 pins rather than just 2.

Finally, here's an image of one of the OC'ed units. The HW error % is a bit high on this, but the unit has hashed at lower rates for longer runs, and also higher hash rates! EDIT: The lower part of the image is the poolside registered rate(s) after OC'ing.



EDIT: It pains me to have to admit that the same voltage OC'ing will apply to the bitmain variants that have the BM1382 chips, e.g the S2 and S4; the reason it pains me is I do not have one!

EDIT 2: I thought I'd also post this to compare with my earlier OC'ing of my batch 6 S3 in this post: https://bitcointalk.org/index.php?topic=750220.0 (also in my signature).

When I ran the test in August 2014 at freq 262.5 with the old firmware, I achieved an average hash-speed over a day of 529 Gh/s with 200 errors (0.00187113284%). Having set the voltage to 0750 in the newer firmware, I have a hash-speed 528.53 and a HW error rate of only 46 HW errors (0.0004%).

So again, not only does the voltage setting aid in OC'ing, it certainly does help with running efficiently!



EDIT: 6th Dec 2014

I had to post this. An update for the 262.5 freq @ 0.75 volts (0750 setting) after running for 2 days. There are only 96 92 HW errors and the % is still the same! The consistency you get from setting the voltage correctly is astoundingly repeatable / maintainable given what we've come to expect of ASIC rigs.

[CapnBDL]

HiYa Peeps,

Been reading this thread from start to here. GREAT INFO. I just got this antMiner S3+ the other day and had it running as of yesterday. Did ALL the .bin updates including the latest from Jan. 2015. HW error levels well within acceptable. (.0046%) Cooking along at 508GH, voltage at 0750 level, 250 freq.

Heres my problem.....I don't know squat about 'putty'. I read the thread on how to enter the other freqs into cgMiner (I have 4.6.1 after the updates). I am clueless. Didn't get how to get into the program...nothing.    I don't know code, Linux, etc. Strictly a Windows guy, or old DOS4.x (yup...I'm old). Heck...actually had a machine with DOS2.something. I was pretty good at DOS 5, Linux baffles me!!

Am I wrong in thinking that if SOMEONE did an archive backup of their firmware, with the cgMiner rewrite, and sent it to me, that I could install it in my S3+ and have it work?
Just saying...hypothetically.

Anyone out there, trustworthy, who wants to be nice?    Doesn't hurt to ask.

And, I noted this description with the latest firmware update:
1. fix bug of negative temperature
2. fix power mistake adjustment.
3. disable VDD adjustment function.
MD5: 3E77FC58E6CF9F6C53510C8154C8B0F9

Is the #3 reference saying that I can't control the voltage with this firmware update. (In which case I'll return mine to the the previous)?

Also, I've been using BTCGuild pool. Is it a good one, or should I be looking elswhere?

Thank you kindly!!! Keep up the good work.

edit: added the description of firmware update

[Mikestang]

Heres my problem.....I don't know squat about 'putty'. I read the thread on how to enter the other freqs into cgMiner (I have 4.6.1 after the updates). I am clueless. Didn't get how to get into the program...nothing.     I don't know code, Linux, etc. Strictly a Windows guy, or old DOS4.x (yup...I'm old). Heck...actually had a machine with DOS2.something. I was pretty good at DOS 5, Linux baffles me!!

I am in your same boat and learned how to use Cygwin to ssh in my S1 and S3+, it's really quite simple, just do a little googling about cygwin and ssh.  If I was at home I could share my links...

[CapnBDL]

Well...I D/Led cgywin and started reading up on how to use it....sheesh! Guess I'll look for putty and see if that's any easier. Can someone give me a clue how I even get into the software on this? Other than the menu that comes up with all the info (config, status, etc.) I can't see anything.


HELP!!!!

Thank You  


edit: OK....so, I'm giving this a try. I installed 'puTTy', and actually got into this S3+. I didn't do any thing dramatic...no worries race fans. I entered the line; /usr/lib/lua/luci/model/cbi/cgminer/cgminer.lua but then it says I don't have permission. Ummm...please don't make me go back and read that long ass thread again. How do I get permission to open and mod the cgminer.lua file?

HELP!!!

Thank You

[Mikestang]

Well...I D/Led cgywin and started reading up on how to use it....sheesh! Guess I'll look for putty and see if that's any easier.

I'll track down the info I have put together, it's really very simple once you know what to do (yea, isn't everything? lol).

Learning to use the vi editor is way more confusing, just wait... 

[aarons6]

what are you trying to do??

the newest firmware disabled the VDD adjustments because very few S3s had the chip that let that happen..

the newest firmware kind of sucks anyway, i use the 12/19/2014 one.


no need to ssh into the miner, all of the over clocking can be done in the menu.

[CapnBDL]

what are you trying to do??

the newest firmware disabled the VDD adjustments because very few S3s had the chip that let that happen..

the newest firmware kind of sucks anyway, i use the 12/19/2014 one.


no need to ssh into the miner, all of the over clocking can be done in the menu.

Guess I'll have to do a reflash. Gotta find the Dec. version. I know Nov. sucked. Want to get in and set up for a higher OC. Menu only goes to 250M. @ 0750v. Should be able to write in the 256M.

Edit: dang file comes up 'Permission Denied'. How do I get it to open?

[CapnBDL]

Well...I D/Led cgywin and started reading up on how to use it....sheesh! Guess I'll look for putty and see if that's any easier.

I'll track down the info I have put together, it's really very simple once you know what to do (yea, isn't everything? lol).

Learning to use the vi editor is way more confusing, just wait...  

Ok...sounds good. I have gotten in /w puTTy but I still get the 'Permission Denied' error. Won't let me mod.

'Till later-

edit: Never mind....I figured it out. I must say...there is some really bad info out there, ie. wrong puTTy cmds, incomplete cmds, just ..well, it can really mess a guy up.

Now...somewhere in this thread, I think, is the info on where cgminer is told how big to make the 'queue'. I would like to set it smaller than the 4096 it's at right now. It's supposed to help with the number of 'discards'. Not sure about the ideal size.

I'm still running the Jan 2015 revision. Last guy said that I couldn't control the voltage with it but when I check on the cgminer process, I see the command line with my input. Seems to be running pretty good for me.  Ummm...am I misunderstanding? Any thoughts?

Thanks for any replies!

[Mikestang]

the newest firmware kind of sucks anyway, i use the 12/19/2014 one.

What "sucks" about it more specifically?  What are the advantages to the 12/19 version?

Well...I D/Led cgywin and started reading up on how to use it....sheesh! Guess I'll look for putty and see if that's any easier.

I'll track down the info I have put together, it's really very simple once you know what to do (yea, isn't everything? lol).

Learning to use the vi editor is way more confusing, just wait...  

Ok...sounds good. I have gotten in /w puTTy but I still get the 'Permission Denied' error. Won't let me mod.

Ok, here's how I did it with Cygwin (might work wtih putty, too? I've never used putty):

1) Follow Part 1, Steps 1-3 here: http://www.wikihow.com/Use-SSH

2) Login with SSH using the IP and username/password you’ve set it to use

Code:

cd /usr/lib/lua/luci/model/cbi/cgminer/

Code:

vi cgminer.lua

3) How to use the vi editor: http://www.cs.colostate.edu/helpdocs/vi.html
insert data from https://bitcointalk.org/index.php?topic=699064.msg8370071#msg8370071
Save the changes, exit vi, type “reboot” (without the quotes) to restart the miner

[Mikestang]

Right on.  I tried mine at 262.5 and it freaked out, had ASICs showing ooo-o-- and hash rates were way down.  I settled at 250 also, nice balance of overclocking without running the machine into the ground.

I don't know anything about queue, sorry.

[CapnBDL]

Right on.  I tried mine at 262.5 and it freaked out, had ASICs showing ooo-o-- and hash rates were way down.  I settled at 250 also, nice balance of overclocking without running the machine into the ground.

I don't know anything about queue, sorry.

Just a big FYI: You actually DO HAVE TO REBOOT after changing freq/volt. Just check your System Log. Scroll to about the 4th line from the bottom. You'll see the line with all your cgminer start/pool info. It also has the freq/volt settings for cgminer. I found out that just doing the Config save/apply button doesn't change the miner settings. They will be whatever you had previously. It's a good check to see what's going on.

Happy mining!!

[tokingtoking]

Right on.  I tried mine at 262.5 and it freaked out, had ASICs showing ooo-o-- and hash rates were way down.  I settled at 250 also, nice balance of overclocking without running the machine into the ground.

I don't know anything about queue, sorry.

Just a big FYI: You actually DO HAVE TO REBOOT after changing freq/volt. Just check your System Log. Scroll to about the 4th line from the bottom. You'll see the line with all your cgminer start/pool info. It also has the freq/volt settings for cgminer. I found out that just doing the Config save/apply button doesn't change the miner settings. They will be whatever you had previously. It's a good check to see what's going on.

Happy mining!!

i think you are right.
after i click save&apply, it feels no change.
but when i turn it off and turn it back on suddenly it has a big change (like lower/faster fan speed).

[CapnBDL]

Right on.  I tried mine at 262.5 and it freaked out, had ASICs showing ooo-o-- and hash rates were way down.  I settled at 250 also, nice balance of overclocking without running the machine into the ground.

I don't know anything about queue, sorry.

Just a big FYI: You actually DO HAVE TO REBOOT after changing freq/volt. Just check your System Log. Scroll to about the 4th line from the bottom. You'll see the line with all your cgminer start/pool info. It also has the freq/volt settings for cgminer. I found out that just doing the Config save/apply button doesn't change the miner settings. They will be whatever you had previously. It's a good check to see what's going on.

Happy mining!!

i think you are right.
after i click save&apply, it feels no change.
but when i turn it off and turn it back on suddenly it has a big change (like lower/faster fan speed).

You don't have to turn it off. A reboot will do fine.

[CapnBDL]

Ok....so I've done about all I can to OC by doing a volt/freq mod. My S3+ happens to love a freq of 250 and volt of 0752. Can't say this holds for everyone but I'm getting ~502Gh. Not too shabby. Still....I want more, so I took a look at cgminers 'queue' size. The default is 4096. After an ssh change to 6144 & 2048 for 6 hrs at each, I was able to squeeze ~4 more Gh out, with the size change to 2048. The 6144 actually gave me poorer preformance.

If someone else would like to try this, please let me know what your results are. I don't make any claims/guarantee. I'm just letting this thread know what worked for me. Anytime I can gain a little speed, it's all good. I push 'till it bleeds...then back off by a hair!  

Happy mining!

edit: Oppsss, meant volt of 0755.
Error on my part.....late night & very fat fingers.   

[Mikestang]

My S3+ happens to love a freq of 250 and volt of 0752.

I did not think voltage was adjustable in 0.001 increments.

...

I looked up the datasheet for the BM1382 chip that is used in the S3+ ...

1. The typical hash rate and power table



...

[CapnBDL]

I've got it set that way....but haven't tested it to find out if it really is. Seems to work out. At this point....hell, who knows.     I've got tooo much time on my hands...lol.

Yup...I saw that sheet too. Just tryin' something out. Might have to break out the meter.

edit: I did notice this little ditty from one of the posts to pekatete;

[/quote]
_{Pete ...!? You talking to me? High fives all over then, and the pleasure is all mine.
I also noticed that the default voltage setting that bitmain ship with is 0725 but there is no mention of any 5 thousandth in the datasheet, so naturally, I tried it on one of my rigs that I had running at 0750 (aka tried 0755) ...... not bad!}
[/quote]

That SEEMS to imply that some of the thousands settings MAY be possible. I'm going back to do further research in this thread. Plus, I need to find out just where to touch my leads for testing 'cuz I don't have the faintest.

edit: upon further reading and strained eyes, I find that there is enough in this post to confuse an average man!! Plenty of info that suggests voltage settings in the thousands MAY be possible but not any specific mention pertaining to positive possibilities. Ok, if you understood that, it means, I don't know. Completely rattled. I think I'll stick to saying that .005s (such as 0755) is doable and refrain from any more jibber-jabber.