The easiest and safest way I found to kick up your ATI video adapter and get a performance increase is with a nicely written, easy-to-use program called ATITool.

It is available for download from ATITool is known to overclock cards with the ATI Radeon 9000, 9200, 9500, 9600, 9700, and 9800 chips, but it should work on other older ATI cards as well. ATITool will test your adapter for both the maximum core video processor speed and the highest memory speed your card will work at reliably. When it finds the fastest and safest values, you can store them away, lock them into the adapter, and have them set every time you boot your PC.

Before overclocking, an ATI Radeon 7000-based video card running at its default 183 MHz core and memory clock speeds in a 533 MHz Pentium III ran at an average of 13.6 fps. Overclocking by 10.3% to 202 MHz provided a performance increase of 12%.

I will post on how to overclock Nvidia Adapter later.Thanks for reading.Have a nice day.