Did you remove the display driver for the previous video card before trying to install the new one? Not doing so will cause problems like you describe. With a new video card and no working drivers installed for it, you are running on basic video drivers and will be stuck with 16 colors until the new card is working correctly. If the ATI instructions are not clear, go to Start>Settings>Control Panel>System and the Device Manager tab. Expand the Display Adapters line and select the line for the old video card and if there also the ATI one at a time and hit the Remove button. Reboot with the ATI CD in and install the driver and any programs you want. This time before you start the install, shut down any antivirus and other programs running. This sometimes help with problems installs.