9cjs shutdown

I've had this home-built gaming and web-browsing only PC for a couple of
years - no hardware changes
9CJS
9600XT
1 gig Corsair RAM (4 x 256)
Sound blaster Live
WD 120G HD
Lite-On CDRW
CBox3
onboard NIC (Realtek 10/100)

A few weeks ago it started to reboot during shutdown. I first noticed
because it would be on every morning after a scheduled night time defrag
(I wasn't gaming during that time period due to external issues). It
would also not shutdown when I turned it on manually.

As far as I remember the only "new" things done around the time this
started was the frequent updating by Microsoft for XP :-(

When I turned off the 'auto-reboot on failure' switch I saw kernal
related faults(tracked down at websites for XP stop codes) that every
website, including Microsoft, said were 99% likely to be caused by
hardware drivers.

I have updated to the latest BIOS (ver 8), video driver from ATI, sound
drivers from Creative, Windows XP default drivers for my Lite-On CDRW
per Lite-On recommendations, ran SpyBot Search and Destroy, Adaware,
latest Norton anti-virus, and cleaned my registry. The only drivers I
didn't update were the mainboard drivers because I felt the instructions
sucked.

If I shutdown from Safe Mode it goes okay. However, if I did a Selective
Start-up (MSCONFIG) and unchecked EVERYTHING the system would hang up on
shutdown again. The stop code might be different (depending on what
items I unchecked) but it was always a kernal related code.

Any suggestions other than a re-install? Would disabling things in the
Hardware tab allow me to isolate the offending driver?

 

After futilely trying all the suggestions I got off this group <sarcasm>
and another dozen or so that I gleaned from the web I ended up
re-installing XP PRO with SP2 slipstreamed into it. So far so good
except for it booting itself everyday at 5am.

I've checked out Task Scheduler and the other wake-up capable programs
that i know of but haven't found anything yet. The BIOS has the Wake Up
On Alarm disabled. Event Viewer is equally vague. Scans by AdAware,
SpyBot, and Norton AV haven't come up with anything either. I'm using
SpyBot to control registry changes and there is no email client
installed on this machine (which is behind a Netgear router).

I naturally want to know this system is under control before I set my
System Restore points and Ghost the hard drive. I'm heading for
Hijackthis now.