my iMac g5 2g 250ghd has crashed 4 times tonight while running leopard. the only thing that seems to be connected to each instance is that time machine was backing up. when i first ran it last night it only backed up 100gb of 180gb. it has continued backing up in stages today. now it seems to be hung up with the preparing note in tm for the past 15 minutes. everything else works great. anyone have a similar issue or have any idea what's wrong? not sure if it is related, but i could also never get backup to work. it always failed to complete the full back up.