This is really really strang problem, I have been trying all the way to fix it, none of them worked. I had DIY experience for over 6 years, but I think only the real pc gurus can explain it.
Here is my pc's symptom: Boot to safe mode, you can normally shut off the pc; boot to normal, even none of any driver is loaded (I mean right after system is installed without Video driver, audio driver ect), shut off will always lead to reboot, and I have to shut it off manually during posting. This is very annoyed problem, and it is very bad to my pc. The only thing I can think about, maybe there some conflicts, but I can not figure it out. Anyone can have a clue, I will cheer for you. You are the real guru.
Here is my pc: p4 2.0G/1G ram/160G HD/cd-rw & dvd-rw/intel 848 MB, run win2k. Thanks