I just build a new PC this week with a ECS 8800 GTS 512mb and everything set up and ran great. I wanted to push my vid card a bit to see what i could get out of it and I followed the guide taking just the GPU core frequency up by 10mhz at a time until I started seeing artifacts. The problem came when I backed the clock rate down. I eventually ended back up at the factory default settings and I still have artifacts. My GPU temp never went over 50C.