my iMac overall has become slow. It took 20min to start up. We're talking a 600MHz iMac G3 here with 640MB of RAM. Funny thing is, the 450MHz downstairs with only 128MB of RAM kills this computer as far as startup and other things are concerned. It was reformatted about a fortnight ago. Permissions have been repaired. Disk utility's SMART info on the HD says "verified".