How do you flash OC a video card?

[RangerXML]

I've got a 8600M GT 512MB DDR2 video card in my notebook and I wanna push it a bit. With the normal drivers the notebook actually comes with software that OC the 475/400 to 500/450, but newer better preforming drivers lock the clocks. I've seen ppl on other forums who are getting good results by flashing with the newer drivers to about 500/500 or 550/500. I'm interested in trying this.

[Guest aebrowne84]

I've got a 8600M GT 512MB DDR2 video card in my notebook and I wanna push it a bit. With the normal drivers the notebook actually comes with software that OC the 475/400 to 500/450, but newer better preforming drivers lock the clocks. I've seen ppl on other forums who are getting good results by flashing with the newer drivers to about 500/500 or 550/500. I'm interested in trying this.

http://forum.notebookreview.com/showthread.php?t=160237

This is the only guide I'm aware of

[colsaunders2]

With some deviation from the guide above, I successfully OCed to 600/450 here. The bulk of the trouble was getting tools that would run on Vista x64 ... no luck with ATiTool, NiBiTor, or the HP drive key boot utility - had to run NiBiTor in WinPE 2.0, and I used the HP usb key format tool with the DOS 7.1 boot files to run nvflash from the flash drive. Oh, and one has to override the "subsystem ID" mismatch reported by nvflash with the '-6' switch.

A lot of work, a bit of danger, but worth it :)