Bitcoin Forum

Other => CPU/GPU Bitcoin mining hardware => Topic started by: klondike_bar on April 07, 2013, 04:42:16 PM



Title: Need some advice for setting up a basic rig with 1x HD 6850 and an AMD 640 core
Post by: klondike_bar on April 07, 2013, 04:42:16 PM
the title says most of it all. I have a HD 6850 and an AMD 2x4 640 CPU. I know neither are particularly powerful, but with the recent value hike of BTC i tink they can turn a profit, or at least be an efficient way of buying BTC with my electrical bill.  ;)

from my research, the HD 6850 should attain about 170-250MH/s for bitcoin at around 130w.  with litecoin it would likely see around 250 kH/s. I would try to underclock the memory and OC the GPU to make the best H/w ratio here.

I cant find much info about the CPU for litecoin mining, but would assume it can operate in the 20-50 khash/s range.



any suggestions or scripting i should use?



Title: Re: Need some advice for setting up a basic rig with 1x HD 6850 and an AMD 640 core
Post by: klondike_bar on April 07, 2013, 04:51:55 PM
So i now have the rig up and running. I have GUIminer running on the HD 6850 overclocked from 775->820 and mem down from 1000->920 with very slight undervolting. It stays around 61 degrees celsius for the most part. With these tweaks, and the "-v -w 128" flags I have gone from a stock ~140mHash to ~200mHash and feel i might get more from a further overclock.

the CPU is running in scryptminer and producing about 4khash per core towards litecoin. (about 15khash average total) This is running with flags : "START /LOW /B minerd.exe --algo scrypt" and I am sure could be further optimised.


any suggestions? Obviously this is not a powerful mining rig, but from my operation so far, seems to be mildly profitable.  (In ~18 hours it has [through pools] mined 6 mBTC and 50 mLTC, and i pay around 9c/kwh)