By default Windows only allows 32-bit color on your computer, which works good for a standard PCI/AGP video card. But of you have a more powerful video card, you can increase your color depth to a higher value. To do this, open Notepad and copy these lines into it:
REGEDIT4 HKEY_CURRENT_CONFIG\Display\Settings "BitsPerPixel"="32"
Change the '32' to the maximum number of pixels allowed by your video card. Save and name the file 'BitsPerPixel.reg' then double-click on the newly created file to enter it into the Registry. Now, restart your computer for the changes to take effect.