slashbinslashbash
Golden Member
- Feb 29, 2004
- 1,945
- 8
- 81
One of my systems is 2-280x and 1-270 and I'm encountering what appears like a CPU related drop in kh/s.
CPU is Sempron 145, Board is MSI 770T-C45 and AM2+ board that runs DDR2.
When I disable all but one 280x I get ~600kh/s and then when I set cgminer to high priority in task manager it gets 710kh/s. Enabling the second one is similar behavior, I need to have cgminer to high priority to get hash rates as high as possible.
When I enable the 270 in a seperate cgminer instance I drop to 670 kh/s on the two 280x's even with cgminer set to high for the 280x's and left to normal for the 270.
The 270 hashes optimally in any situation.
Could this be related to the g 2 setting that i'm using in the cgminer settings for the 280x's? I know that on my multi core systems i'm not getting the same drop in kh/s on the 280x when cgminer is at normal instead of high.
I'm able to get the hashing rate up as well by disabling cool n quiet in BIOS so that the Sempron runs at 2800 vs 800, but still nothing I've tried has got the 280x's to hash the same without the 270 as with the 270 running.
Could it be a power supply issue? From your description, it only seems to happen when you've got all 3 cards fired up. Are your voltages staying stable?