Got mine stable at 925/1200 w/ no artifact or heat issues using Trixx. I Set up the voltage @ 1.20 on the dot. On my system an increase to 1.25 v did nothing but raise the temps. It actually lowered my 3D Mark score from 21,400 to 21,000 using a 950 core clock speed at 1.25 v. It seems the best combo is 920-925 core and 1200-1215 mem clock. That is where I got my best scores on 3D, Fur, and Kombustor. Only Furmark will take it to 80 C. Hardcore gaming for several hours never took it out of the mid 60's on 75% fixed fan speed which is not that loud. Oh, and I too had the voltage issue. I had to go to msconfig and disable CCC from starting at boot up. I then changed my voltage settings for my PCI-E slot in my Bios itself. Most good overclocking motherboards will allow this. Then you dont have to worry about messing with your voltages in Trixx. Just make sure you monitor it w/ Trixx's GPU monitor gadget or GPU-Z to be sure.
Edited by Zigs6 - 6/11/11 at 2:47pm