The monitor itself is purple?

Try hooking up a different monitor to the computer to test if your monitor is bad. The monitor may not actually be bad, it may just need to be reconnected to your video card. Sometimes this happens if a pin or two become disconnected.

Also, it may be your video card or video card drivers. You may have to take it in if thats the case. If you don't want to take it in, my company offers remote access!