Blank Screen On Startup In Tiger 10.4


I am a fairly knowledgable OSX user. I am working on a G4 dual 1.25. I just bought this computer on ebay a little over a month ago and it came with Tiger installed. Basically, I attempted to burn a CD. When Toast launched, the system froze up, and on restart it gave me a blank screen. I can still find my hard drive through the network and everything still seems to be intact. The computer didn't come with any software, so I purchased Tiger and tried to repair permissions but that didn't work. I also ran the updated DiskWarrior for Tiger, but again no luck. Any help would be greatly appreciated...