I just replaced my 2900xt with a 8800gts 512 and wanted to see how well it overclocks. I installed rivatuner 2.06 but when I click on customize to overclock I dont have anything except for low level refresh settings, desktop schemes and diagnostic report. I have the lastest Nvidia driver(169.25) installed. I tried reinstalling both the driver and rivatuner. Is anyone else having similar problems?