Is there a blue tint even during post right after you power the computer on? If so, it's either the vga cable or the monitor itself. It's not drivers for sure... If it's only doing this for that specific omputer and the monitor and cable work fine on another computer, the only remaining variable would be your video card.
So if you are able to get your hands on a different monitor, try a different monitor on the same PC. If you're having the same problem with the new monitor, try that monitor with a different video card on the same PC. If putting a different monitor with the same PC fixes the problem, the problem lies either with the monitor or the vga cable.
I hope this helps.