colors look fluorescent and lots of horizontal shadows
take the monitor and plug it into another computer. If the same symptoms occur, the monitor is failing. If not, the video card in your computer is having the problem.
It sounds like the monitor has gone bad, but something else that can help is to delete the old video adapter drivers and reinstall with the latest version.
Most (if not all) modern LCD monitors (or CRT monitors for that matter) have a control panel consisting of three or more buttons on the front that can be used to access the menu system contained within the monitor's firmware. I would suggest that you access your monitor's internal configuration screen. If this looks clear and the colors are true then it is a problem with your computer's hardware and/or software - OR - your monitor's video cable. If the setup screen itself looks funny or off then it is the LCD display which is failing.
