CGminer Overclock for Antminer

InquiringMinds

I really can't find this answer anywhere.   How do you overclock the AntMiner U2  to 2Gh/s with CGminer?

FabulousPanda

I believe you use the flag 

--anu-freq 250

InquiringMinds

i have tried that flag and it doesn't seem to be working.  My Antminer U2 is still running at 1.6 Gh/s

FabulousPanda

Have you tried using bfgminer instead? In that you use 

--set-device antminer:clock=0981

default is 0781 and in between 0881

InquiringMinds

yes, bfgminer does work for overclocking.  I just encountered something that made it stop hashing after a couple hours.  Also, now it says it's hashing at the correct speed but it's barely submitting any completed blocks.

FabulousPanda

Is it represented properly by the pool? I wonder whether even 2Gh/s is getting slow these days… 

InquiringMinds

That's the problem.  BFGminer says i'm hashing at 2Gh/s but it's not sending completed pieces.  I left it on for an hour and it's submitting 10% of what cgminer is doing.  I have a feeling it's the silicon labs VCP drivers because it says on their web site that it was never updated for OS 10.9.

FabulousPanda

I'm using one fine with bfg - was yours working fine with it until now?

InquiringMinds

I only got BFG working a couple days ago.  The first time I used bfg it stopped hashing after a few hours so i switched to CG.  

Is there really no way to over clock CG in MacMiner?

FabulousPanda

I would have thought cg would support it, but the ASIC.README only says 

https://github.com/ckolivas/cgminer/blob/master/ASIC-README

--anu-freq <arg> Set AntminerU1 frequency in MHz, range 150-500 (default: 200)

Note it says U1 but U2 and U2+ I believe should work the same

You could try a higher frequency?

FabulousPanda

I wonder whether this is the problem you're having - might explain the low accept rate from bfg:

By default, Antminer U1 devices run at a clockspeed of 200. This command allows

you to specify a chosen frequency to attempt to run all ANU devices at. Cgminer

will try to find the nearest frequency the device supports and will report if

the frequency is not exactly as requested. Note that cgminer reports hashrate

ONLY FROM VALID HASHES so if you increase the frequency but your hashrate does

not increase or it decreases and hardware errors start showing up, you have

overclocked it too much. In the worst case scenario it will fail to start at too

high a speed. Most will run happily up to 250.

In which case, probably best to try a lower frequency first.

FabulousPanda

Quote from ck, dev of cg:

With the official cgminer, use only --anu-freq and nothing else.

Obviously, he intends you to use a number too, e.g. --anu-freq 225

I wonder whether this is a hardware problem... 

InquiringMinds

Update:

Things seem to be working fine in BFG miner.  I even over clocked the U2 to 2.2Gh/s with no hardware errors after 2 hours.

I just re-installed the drivers and set the block difficulty to a much lower level.  It seems BFGminer likes to start out with large block sizes.

Ground Lem

> FabulousPanda > I would have thought cg would support it, but the ASIC.README only says  https://github.com/ckolivas/cgminer/blob/master/ASIC-README --anu-freq Set AntminerU1 frequency in MHz, range 150-500 (default: 200) Note it says U1 but U2 and U2+ I believe should work the same You could try a higher frequency? I am new here ... and i would like to know how can i OVERCLOCK my Antminer U1 to hash at 4Ghs?I have tried the code " --BMSC-FREQ 5381 " but i get a error, so what is the correct "bmsc-freq" code and for what version of CGMINER?