I just went through the firmware update (v.4.4.8) which the weekly software update found and after restarting (holding down the power button until I got the long tone, as instructed) my machine went dead! I didn't even have a signal to the monitor until I zapped the PRAM and now it gives me the little "timeclock" circle endlessly. I tried re-installing the system but the installer freezes up at the "preparing the disk" screen. What the heck did I do?