Windows hangs during shutdown or log off

[prabhats]

I have this problem from about 2 months, when I shutdown from XP the mouse hangs and everything freezes, even the HDD stops. 1 month ago I sent my HDD for repair as I thought it was the problem, seagate returned a repaired HDD 1 week later. I reinstalled everything back and now the problem has started again. sometimes it also shows an "Unknown hard error" and hangs during shutdown or log off. and sometimes it freezes during normal operation if the comp is left idle for too long.
plz help as my frustration it crossing limits.
i'hv tried reinstalling the drivers and uninstalling the programs which on opening caused hangs, but the problem remains.
the rams are OK memtest86+ shows no error even after 2 hours of running
is it an HDD problem again, or the motherboard is faulty?

config:
AMD athlon 3000+ venice
Gigabyte GA-K8N51GMF-9
XFX 8500GT

 

[robisbell]

Motherboard Manufacturer and Model:
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RAM Manufacturer/Type/Model:
CDRW/CDROM/DVD Manufacturer and Model:
Disk Drive(s): Manufacturer and Model:
Video Card: Manufacturer and Model:
Sound Card: Manufacturer and Model:
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Operating System:
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