a lose connection with your monitor or graphics card - make sure all lead are firmly connected - and if you know how to open your computer up, make sure your graphics card is properly in its socket (thats if it is not an integrated graphics card).
If it still persists it maybe one of the above on the way out - try using a lower refresh rate and check to see if you are using correct drivers - eg not just a "plug & Play" monitor - it must specify your monitor name - you can do this in display properties - then settings then advance then monitor.
Its not likely if these items are faulty that they will do damage to each other or other hardware but famous last words - if there is "short" somewhere this can do damage.
I have some sort of unidentified hardware malfunction that causes no other problem other than making everything that is white on the screen appear bright teal. This flicks on and off at random and I can deal with the inconvenience if that's all it will be, but will it cause a problem elsewhere in my computer? Can one piece of bad hardware fry the whole thing? Thanks very much.