I know this is a very tough nut with many possibilities. XP shuts down fine but instead of powering off it just freezes at the "saving your settings" screen once the harddrive light stops flashing. Just coincidentally, this started not too long after I took Speedstartup of my system.
It powers off fine in Safe Mode. I've tried lots of suggestions about unloading drivers to see if I can come across the conflict, but no luck so far. I didn't unload what appear to be system drivers, not wanting to really screw things up.
Any ideas out there for being more methodical about this?