The first thing to do is to check the 'enable low-level hardware overclocking' box to enable the sliders below.

RivaTuner needs to determine the card's default clock settings before it can proceed. Assuming that no other overclocking software has been used on the ATI card, click the 'detect now' button. Otherwise allow the program to reboot the system and perform the detection.

Now that the core clock and memory clock sliders are accessible, overclocking can begin. The two small arrows delimiting a section of each slider provide a recommended overclocking range, but the best bet is to increase the settings gradually, benchmarking at each step (see the benchmarking section below for details on this). Each new setting must be confirmed using the 'test' button at the bottom of the window before it is set permanently.

Remember that just because the overclocked settings pass this test does not mean that they will work with real world games and benchmarks.