Sometimes, when I wake up my computer from a screen lock, one of my screens is inverted. It does not always happen (maybe one in ten times) and it is not always the same screen. Re-locking and unlocking the screen a couple of times fixes the colors again. I have a dual monitor setup on an ATI Radeon HD 3450, using two HP screens connected over DVI. I am using the radeon driver, and according to jockey there are no additional drivers available for my system. Any ideas as to why this happens?