Mining speed of Nvidia GT 640

[tra95]

Is it normal for my card to be mining at a max of around 23Mh/s?

I understand that for nvidia cards, I should be using a cuda miner. However, all miners I have tried, poclbm, bfgminer and rpcminer-cuda all hit around 23Mh/s.

I have also tried running rpcminer-cuda with -gputhreads 384(384 from here, I have a GT 640 128-bit DDR3), but it does not change anything.

[John (John K.)]

I'm not too sure about that specific card (you'll have to consult the hardware wiki for that), but Nvidia cards are generally slow and inefficient in Bitcoin mining.

[tra95]

I know nvidia isnt the best, just trying this out. I have checked the wiki and googled, there is no mention of my card anywhere :/

[John (John K.)]

Looking at hardware comparisons, 23MH/s for a 640 seems on par. A 540 gets like 16 MH/s so ...

[tra95]

I see...alright. Just curious, because I know a 560 gets 75~MH/s.