Hi this is my first thread on this forum.

Recently my pc is behaving in a strange way. It simply crashes randomly and without warning.

When it happens the pc stays like this:
. power led on
. hard driver led constantly on
. no screen output (monitor warns there's no signal)
. ctrl+alt+del nor reset restart the system
. cpu cooler and psu cool are spining
. if I try to open cd drive it does nothing
. internal motherboard led on

My only choice is switch off the psu and then switch it on, so the system would restart. The crash happens on these situations:
. after the showing of the bios screen
. before starting windows gui
. while windows is working (everytime I play mp3 files or movie files)

Sometimes the system works for several days without any problem, if I don't play those files.

PC specs:
CPU: AMD Duron ~1Ghz

256MB DRAM

Motherboard:
Gigabyte GA-7ZMMH
S3 Savage4 (on board)
Creative CT5880 PCI (on board)

Drives:
floppy drive
SAMSUNG SV3063H 30GB (primary master)
LG CD-ROM CRD-8522B (secondary master)

Cards:
Lucent Modem E150984 (slot1)
Micronet SP2500R (slot3)

PSU:
Task Tk-925TX

OS: WinMe, Win2000-SP4, WinXP-Pro-SP2
(I installed these OS each at a time, formated the drive between installs)

The hdd file system is FAT32. The problem occurs on all those OS. Scanned for virus using Panda Titanium and AVG 7.1, but found nothing. I used Ad-ware and Spybot to check spyware and all that nasty ***, they only found cookies. I used memtest32, but no error were pointed.

I run a Gigabyte utility to check pc inside temperatures, mem use and disc use, it show that the CPU temp is about 51 degree Celsius and the system temp 32 degree Celsius.

Any sugestions? Thanks.