Two cards, same settings, radically different hash rates? [solved]

[Tamerz]

I have two 6970's currently running at stock speed. Using GUIMiner, I am getting around 360 - 370 Mhash/s on one card, but only around 310 on the second card. Both are using "-v -w128 -f0". Any ideas why this would happen?

EDIT: Tried a good old "fix it all" reboot, and both are now in the higher range. Very strange.

[gigabytecoin]

Could have been simply your mouse movement or other background display graphics perhaps that were messing with one card's mining speed.

You will get best results from dedicated miners that do nothing but boot up and mine.