I installed Tiger (clean install) on my G4 (350mhz PCI Powermac, 640mb ram, Radeon 7000 32mb) a few days ago, seemed a little slow, but otherwise fine. Now suddenly the Finder menu bar is slowly flashing on and off, the files that were on the Desktop are gone, and applications won't open, or open briefly and crash. I shut down and rebooted, but no change. Any suggestions?