I have ran every scan for viruses and malware. My computer is clean. HD
crashed a month ago (new computer, under warranty) so new HD was reformatted
and windows reinsalled (by HP authorized repair station) Problem started
occuring before the old HD crashed so it does not appear to be HD related.
repair station also ran antivirus and spyware scanners and found nothing.
They also checked all the hardware and found no problem. Previously system
froze randomly every few days to few weeks. It is now occuring every 1-2
days. Computer was new in february 2005 and started freezing in september
(once a day at random times and never on startup) ctrl-alt-del does not
work when frozen - I have to power off. It reboots fine. freezing never
happens at restart - and does not matter what programs are running. I
contaced HP and did everything they suggested including checking for
conflicts, limiting startup programs, checking every hardware installed,
running scandisk and defrag (200gig HD 94% free space) I only use one
antivirus program and have tried different anti-spyware programs and
uninstalling the old ones thinking there may be a conflict (doesn't matter -
freeze happens no matter what) I scan for viruses and spyware every day
(Norton - and online scans at trendmicro and pandasoft regularly) I have
checked the security on my computer at various sites and it says my computer
is extremely secure. Recently upgraded RAM thinking it may be a memory
problem (went from 512MB to 1.5gig) processor is 3.2gig I connect wireless
on an extremely secure router (and have since july - problem did not start
until september) None of my files are shared and intrusion detection is very
secure. Computer freezes at random times with different programs - does
not seem to be ryhme or reason to it. Ran eventvwr after restart and does
not seem to show a problem. There is no conflict when I check for hardware
conflicts. I made sure my wireless network connection is the only one
enabled. Techs cannot find any problem and I did everything HP online
support suggested. ALL of my windows (XP home) updates are installed -
including the optional updates. This problem continues even with the newly
formatted new HD so I don't believe it's the HD or corrupt windows. SP2 if
that matters. When it freezes, there is no error screen or no way to get to
the task manager - must power off to reboot.

Here is the specs on the computer:

HP Pavilion a820n desktop WinXP SP2 (completely updated)
3.2gig processor
1.5gig RAM (just upgraded from 512MB)
200gig HD (94% free)

Only hardware upgrades since new was the wireless card (linksys) and the new
HD after the HD hardware failure (repair station installed, formatted and
they reinstalled the wireless software) and the 1gig RAM although problems
started before the new HD and the RAM upgrade.

Freezes even happen within a few hours of running scandisk / defrag and
knowing there is no viruses or malware (I was completely scanning everything
when it first started freezing thinking it was viral related) I am a fanatic
keeping viruses, adware, and spyware out (repair station says my computer is
the cleanest they've seen)

I am out of ideas on what could be wrong and how to fix. Every time I
thought I found the problem, it continues to freeze up. Never more than once
a day (so far anyway) Minutes to a couple of days after reboot (usually at
least several hours)