I've got a comptuter with a 15" NEC LCD and a really old 2mb PCI video card. If I look really closely at text, it seems to "vibrate"...I can't think of any other way to put it. It just gets kind of blurry and then goes back to normal a couple times a second. It's hard to notice unless you really concentrate on one word. Is this something wrong with my monitor? Or my antique video card? Or something else?