OK. So, I just got an Apple A1006 DVI to ADC converter (thanks TreeSemdyZee!) on Saturday. I'm really happy because now I can pull my NVIDIA GeForce 2MX and install my ATI Radeon 9800 Pro (thanks OrangeSVTGuy!). This is a long story but I'll cut it short. Apparently my current PSU is insufficient to power everything and run my current CPU card at 1.73Ghz at the voltage I am asking for. I discovered this through numerous non-starts, restarts, Giga Designs software reinstalls and firmware flashing. Even if I could get the Mac to boot it would crap out before it hit to login window. Yet, my Sonnet 1.2Ghz single processor was rock solid! So, I finally decided to fool around with the settings on the dual. I set it down to 1.6Ghz and reset the voltage to 1.5v. After a few non-starts it came up and I went right to the login window! So, unless someone has any different ideas, I am assuming this is due to the fact that the CPUs are asking for power and the PSU can't deliver. The Radeon 9800 Pro has an additional Molex cable even though it has AGP power. So, I guess it's drawing a lot. The curious thing is that I removed two fans AND put the old NVIDIA card back in and still had issues. Although, I suspect that was after I reset the PMU which probably wiped the firmware. In any case, I seem to be stable at 1.6Ghz (dual). I'm fine with that for now since it means dual processors and my Radeon (with the A1006). I'm now pretty serious about doing an ATX power supply mod. The easy thing is that there is a guy on the net that sells the power cables that connect the ATX supply to the Quicksilver logicboard. Since this is something I want to do anyway I'm probably going to play with the processor speed again and see what happens then.