For a month or two now, whenever I press the print-screen button in order to take a screenshot, it just freezes my computer and forces me to restart it. I noticed it sometime around when I disabled driver signing in order to use Virtual Audio Cable, however I re-enabled it just recently and it still freezes my computer. As far as I know my drivers are functioning just fine and I don't have any viruses, though a virus would most likely not be the cause of this. I am running Windows Vista 64 bit. If you need any additional information, just ask.