So--I've hooked back up the trusty G4 after I couldn't get my G5 to boot. I've tried both the SATA ports and they aren't recognizing drives at all. First, it was just rail A that wasn't working, and now B isn't either. I'm actually a little glad to be using the G4 again, and it actually holds up quite well by comparison to the later-model PowerMac. I opted for an SSD as the boot drive this time and surprising, it seems a lot faster than the WD 7200RPM SATA III drive that I was using previously. Edit: Also, if anyone is interested, while I was configuring the G4 I decided to test my G5's OEM Radeon 9650 (256mb RAM, Dual-Link) and it worked automatically with no drivers necessary. After testing the 9650, I reinstalled the FireGL X3 after downloading the 4.5.7 drivers from ATI).