Hey, I've got an 08 Mac Pro with a 30" ACD hooked up to it as well as a 24" Apple LED display (via a MDP to (DVI?) converter) and I'm having some problems. Basically, sometimes the screens go black. It can be when the computer turns on, that one (never both) doesn't turn on... or, when waking from sleep, or, one just goes black at some point. I ran TechTool Deluxe on the Mac Pro and the GPU passed the test just fine, I'm wondering why this is happening? FYI The converter is USB powered. Any thoughts?