When you install Windows 7, the driver for ATI Radeon card is installed automatically. With the default driver, you cannot overclock the card. You need the ATI Catalyst driver. The download web site is here.
Once you have downloaded and installed the package, follow the steps.
- Press Start (Windows key) and type CCC. CCC – Advanced will be shown in the program list. Click on it to invoke it.
- Click on ATI Overdrive.
- Overdrive is locked by default. Click on the padlock to unlock it.
- You can now overclock the card manually or click on Auto-Tune and let the program select the best settings for you.
On my Radeon HD 4830, I can overclock it to 680MHz GPU clock and 1135MHz Memory clock.