Help: Low Hashrate in a 7850 GPU with CGMiner

[vingaard]

First of all, I'm sorry if I post in a incorrect section (and also I'm sorry for my poor english )

I have a 7850 GPU running in a i5-2500 (3.30GHz) Windows 7 64 bits machine, and I'm using CGMiner 3.3.1 and I can´t get more than 220 MH/s with next configuration:

cgminer.exe -o http://pool.50btc.com:8332 -u **USER** -p **PASSWORD** -I 12 -Q 0 -s 1 -E 5 --thread-concurrency 8192 -g 2 -w 256

I have test a lot of configurations and I can get a slighty higher hass rate whether I increase -I 13 (more of this value the GPU will crash)

Could anyone help me with a best configuration for this GPU card?

Thanks in advance

[TheSpiral]

The same thing with -g 1 should get ~310 MH/s.
You also don't need the thread-concurrency for SHA256 mining...

[vingaard]

Thank you for your answer...

I have test your configuration and I get 213.3 Mh/s... I don't know why?!!! or what I'm doing bad... I have read that this kind of GPU can reach 300 Mh/s, furthermore, with GUIMiner I get 280-300 Mh/s but I can't do the same with cgminer...  

Anyway, thank you and if you think in other option I will try it.

[TheSpiral]

Thank you for your answer...

I have test your configuration and I get 213.3 Mh/s... I don't know why?!!! or what I'm doing bad... I have read that this kind of GPU can reach 300 Mh/s, furthermore, with GUIMiner I get 280-300 Mh/s but I can't do the same with cgminer...  

Anyway, thank you and if you think in other option I will try it.

Here is my setting for cgminer, it's a bit different than yours (your settings are good for scrypt mining, not SHA mining):

Code:

cgminer -k poclbm -I 6 -w 256

I run 2 7850's that do 315 MH/s (each) with that exact line.

EDIT: So your full line would be:

Code:

cgminer -k poclbm -I 6 -w 256 -o http://pool.50btc.com:8332 -u **USER** -p **PASSWORD**

[vingaard]

Thank you very much...

After a little search and another little "try and error" with different parameters I finally setup a configuration file that give me 300 Mh/s average... (and doesn`t crash the GPU...)  

{
"pools" : [
{
"url" : "http://pool.50btc.com:8332",
"user" : "USER",
"pass" : "PASSWORD"
}

],

"intensity" : "12",
"vectors" : "1",
"worksize" : "256",
"kernel" : "poclbm",
"lookup-gap" : "0",
"thread-concurrency" : "0",
"expiry" : "120",
"gpu-threads" : "2",
"hotplug" : "5",
"log" : "5",
"queue" : "1",
"scan-time" : "60",
"temp-hysteresis" : "3",
"shares" : "0",
"kernel-path" : "/usr/local/bin"
}

Anyway, thank you very much for your help and best regards...

Thanks again