I'm trying to help a professor at school troubleshoot a DA G4 that he's trying to get running to operate an instrument computer. As background info, it's a single 533. It has 1gb of RAM in two 512 sticks-one is the brand that shipped with Apples in this time period(I forget what it is) and the other has an OWC sticker on it. The video card is a Radeon 9000. In any case, the computer will boot to an OS 9.2.2 desktop. Once booted, however, it will lock up. The cursor will move, but nothing else works-it doesn't respond to mouse clicks or keyboard input. Booting without extensions clears this problem. It also boots perfectly into OS X(I'm not sure what version, but I think 10.4) with none of the above issues. I formatted a hard drive and did a clean OS 9.2.2 install in my own Digital Audio. Booting off of this hard drive causes the same symptoms as above. I'l also add that we have done a PRAM and PMU reset at several points along the way, none of which cleared the problem. Any idea of what could be going on here?