Hi,

My setup:

Intel Q6600
Asus P5K-E (a 16x PCI-E slot & a 4x PCI-E slot)
Antec HCG-900
Sapphire 6970 (x2, no crossfire cable connected)

Driver version 8.85-110419a-118226C-ATI

I'm using Catalyst Control Center (latest drivers) and Trixx.  I've read elsewhere people underclocking their 6970 memory way down to 500, but CCC doesn't let me go any lower than 1375.  In Trixx, I can set the memory to 500, but I don't think this is being honored; using GPU-Z shows the memory speed still at 1375.  Is there another tool I need to use?