r50e automatically restart after windows loaded

[realdan]

IBM thinkpad r50e
Windows XP home edition

After windows loaded and all the IBM related services are loaded..the laptop shutdown by itself(*its shutdown is like when the power is lost) and restart

It doesnt happen in safe mode.

What I have done so far.....
scanning for virus or spyware in safe mode doesnt yield anything
I have restored the system using IBM access

All tha above cannot solve the problem.

A peculiar thing is the system doesnt shutdown by itself when a USB flash drive is connected.
As soon as i removed it, it shutdown like i have said before
I cant comprehend what is wrong?

Somebody please help me out...

[jfsmith]

It sounds like a corrupt driver. Check the System Log in Event Viewer. The problem might be USB-related, so I'd also suggest uninstalling the USB Root Hubs in Device Manager, reboot and let them reinstall themselves.

[realdan]

well once windows loaded and with the USB flash drive still connected, i uninstall the said USB root hubs.
When i removed the USB Flash drive, it has no problem
but after a restart, windows re-install the driver and the problem persists

[realdan]

Update:
it no longer restart by itself nor does windows xp reinstall the drivers when i disable the USB root hub