[Johnj]

First turn on a light.

If you are running Windows go to thier update site and get all the updates for your OS

You may have to go to the web site of your video card manufacter (like ATI or Nvidia ) and download the latest drivers.

If your don't know what video card you have click Start, then Run, and type dxdiag, then press Enter. Wait for the program status bar, then click on the video tab. The card type and driver are listed there.