I've got this strange problem with X, occasionally after the screen blanking comes on, the system hangs when I move the mouse. The screen comes back but nothing works, the keyboard is locked and best of all, so are the hard-drives. In fact the only way to get out of this lock is to hit the reset button. However...at this point neither hard-drive is visible, the lights are on but they're just freewheeling. The ONLY way to cure the problem is by physically disconnecting the IDE cables from the drives.
I suspect that this is not normal. If anyone has any suggestions I'd appreciate it.