All screens go black and PC freezes when I turn off a monitor connected by HDMI. I can tell that it's frozen since NumLock does not toggle any more. Power-cycling the PC brings things back to ...
I just got a new video card (AMD ATI Radeon EAH5450) and new monitor (Dell E228WFP). Overall they work great except black pixels over a light-blue or gray background (e.g. text on a light background). ...