I have always lusted after PowerMac G5s, so recently I bought one off eBay, a nice, clean, Late-2005, 2.3Ghz dual core. So of course I have to tart her up a bit, maxed out the memory, a 2Tb hdd, and a NVIDIA Quadro FX4500 card. I use a 43" Vizio Ultra high def tv as my monitor. When I first turned it on after replacing the 6600 card with the NVIDIA Quadro FX4500 I thought the card was defective — I got no screen display from either DVI — I mucked around for a bit but couldn't find anything wrong. Then I decided to share the screen with my iMac, and the G5 running OSX 10.5.8 was seeing the FX4500, but for some reason it wasn't displaying on the 43" Vizio. I switched DVIs and when I couldn't think of anything else to try I connected an old monitor to the FX4500 and I got the G5s display, and when I did that the Vizio tv also got its display working. But I don't need the old monitor plugged in, just connected to the FX4500 with a DVI cable. It seems like I have to have that old monitor connected to the FX4500 or the display on the Visio blanks out. I would really like to eliminate that crappy old monitor, anyone know what the problem is and how to fix it?