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hi i have an issue with overclocking the antminer u1 but i cant post int he form i have an really important issue to discuss.. it overclocks to 2gh/s when i set the freq code but when i set the freq code to mine at 2.2gh/s it reverts to the default 1.6gh/s this is with the BFG miner 3.10.0 i switched to bfgminer because its more stable than cgminer cgminer wont detect multiple usb erupters unless i mess about and plug each one in at a time however it did mine a 2.2 for each erupter connected now i can only mine at 2.0 using bfg but the reason why i use bfgminer is because it auto detects the erupters so i dont have to mess about plugging them in and mess about with slicon drivers etc..

help me in the right direction please


examples

--set-device antminer:clock=x0981    this works at 2gh/s
--set-device antminer:clock=x0A81    this doesnt work at 2.2gh/s it reverts back to 1.6gh/s


this is with the bfgminer

I'm also interested in this.

+1 from me

I've had the same problems.  It's annoying because I have two fans on them so they can run a lot higher.  Thinking of switching over to cgminer.

When trying to overclock it I will get like half of them not showing up then I have to restart it until they appear again.

Some people have written that they are hit-or-miss with overclocking beyond 2GH/s --without-- changing the resistors.
It may be that the voltage needed to overclock simply isn't there with all hubs/connections/some other speculative answer.

The answer may lie in the fact that with stock resistors the device is working on 0.8v.
If you change the resistors to allow a supply of 1.0v through the device it may overclock with no argument.

Just a thought. Also, I found it pretty cool that Bitmain would supply this kind of information without being asked.

Sorry for crappy answer. I'm sure it's not the answer you were looking for  :-[

Do your hubs have enough power?

I can't overclock at all my antminers, with bfgminer. Every value I put I obtain always 1.6 Gh/s. Tested with --set-device antminer:freq=x0881 and --set-device antminer:clock=x0881.
P.S. what is the correct, "clock" or "freq" parameter? (I use Raspberry Pi with raspbian OS)

you need to do modify the hardware to go over 2Gh/s , I think it requires replacing a resistor

I've replaced one of my antminers with 0603 10K OHM and 4.99K OHM SMD resistors. I have been able to overclock it successfully to 2.5GHz, but it doesn't go past that without giving a lot of hardware errors. I'm reasonably sure this is an issue with cooling on the ASIC. I will attempt to work out a way to diffuse heat better and see if this yields better results.

Has anyone else tried this?  ???

hi,

Here my conf with BFGMiner 3.10.0 on rasberry-pi in my mind. I have antminer U1 and U2 on same usb hub and work at 2ghz.


have fun

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