Just a thought. I noticed that when I originally used the autotuner for my ATI card that it was set around 710 clock speed (original clock speed was 700) and then when I boosted my cpu to 3.8 ghz and retuned the vc it went to 740 clock speed. I then read an article that talked about the relationship between the cpu and the vc. It seems that the auto tuner somehow adjusts to the speed of the cpu up to a certain point. More than likely based on heat, card limitations or cpu limitations. From the article I gathered that the card will limit itself to the point of the where the bottleneck occurs. Now I'm not savvy on this subject. I justed wanted to put this out there for commentary. Maybe I will learn something. Oh, haven't adjusted the card since going to 4 ghz.