I recently bought a ASUS AMD Radeon eah50 5450 silent video card, The thing is it works in my older tower, but not my new one. There are not any compatibility issues either. It wont let me install any drivers because the video card needs to be in device manager. I can plug my video card in but when I plug in my vga my monitor goes to sleep. So the card works perfectly in my other pc. Can anyone please diagnose the problem please? Thanks.