Jamie

Saw this behavior even before Norton was installed, so I don't think it's the
primary cause. Not using Norton Suite, just Antivirus. Tried Internet Suite
when it first came out (a year or two ago maybe) and promptly returned it to
Symantec because the performance was so poor. Luckily, they allow a software
return since I bought directly from their online store.

I had trouble when I first installed the SIG SATA controller card and Vista.
Within a minute of booting, it would start acting like a process was hogging
the CPU (mouse would jump occassionally, but I could never get enough control
to diagnose). Boot into safe mode and it would work fine.

I suspected an IRQ conflict of some sort, but nothing was indicated in
device manager. I think there's some device that doesn't like sharing an
IRQ. I decided to move the SATA controller card to a different slot anyway.
Once I did that, it started behaving much better. But still see the lock ups
every few days.

I will try the other things you suggest.