We have a strange problem with our computers at my school. They are all Latitude 2100 Netbooks. At random points (I can't seem to find a pattern) the screen will turn a single color (red, green, black, brown, etc.) To fix this, the computer must be put to sleep, and brought back up.

They have integrated graphics, but I can't imagine that if it was a bug with the computer itself, that every single computer would do this. Is there any way I could find out the problem that's causing this. Some diagnostic tool? Thanks.

Edit: Forgot, they all have windows.