My boss and I both have DP 1.8 GHz G5's. Since updating to 10.3.5, our computers have been buggy. For me I use Missing Sync to sync my Palm and now whenever I try it crashes my G5 to a black screen with the different languages saying "manual restart required". Both of us have had restarting issues to. We'll go to restart, it comes up on the screen with the apple logo, then hangs, then the fans start going, faster and faster and faster, and the computer sounds like it's getting ready for the next Mars mission. We turn it off, then restart it again, and all is OK. Any word from Apple, on WTF is going on with this. I run 10.3.5 on my PBG4 with no problems. Very odd!!