Bitcoin Forum

I have a x58 based rampage II extreme with an overclocked i7 920 (@3.6) with memory at 1600mhz

2x XFX 7970 @1.0V, 1000mhz core, 1500mhz memory

using cgminer with mostly default settings, mining LTCs , with thread-concurrency set to 22400 and nothing else

using catalyst 13.3 beta3 (same results as 12.8 and 12.10)

I can't get past 520kHash/s per GPU @ intensity 13

any other intensity and hashrate drops to ~200-300khash/s

overclocking the gpus even further gets a few extra khashes at the expense of more power consuption. this balance of power/noise and hashrate is the most efficient for me


my friend has as similar configuration, but with a Z77 based motherboard and a i7 3770k

he can get 620kHash/s per GPU @ intensity 18 (same GPUs, same clocks, same cgminer/drivers/windows version)

does the mobo/cpu combo has such effect on hashrate and acceptable intensity?
what is in fact intensity?
does PCI-e 3.0 makes a difference ?

Try settings from here https://github.com/litecoin-project/litecoin/wiki/Mining-hardware-comparison#wiki-ATI_AMD_GPUs

Processor doesn't matter in this type of situation, I have I5 3570k on idle while mining and two 7950. One giving out 730khs and other 620khs (could be 700+ if they weren't so close in my case)

To get better hashrate speed you have to spend some or a lot of time trying to overclock and tweak settings, but anyways check out that it should give you enough.

Intensity idk really (newbie) but I think it's for how much % usage you're letting the program to use your card. For 7970 I think for some reason the best intensity is 13.

No, PCI-E 3.0 doesn't make any difference, in fact, some people are running their GPUs from just PCI-E x1 with special risers/exension cables (x1 to x16)