ASUS M2N-E - repeating shutdown

[Smaug]

Hi, I have issue with my system:

ASUS M2N-E
AMD Dual-Core Athlon A64 X2 3800+
512MB DDR2 667MHz PC5300 CL5 KINGSTON
Leadtek WinFast PX7600GT TDH

FORTRON 400W ATX
ARCTIC Freezer 64 PRO
CoolerMaster Centurion 5

It repeatedly shutdowns (like if you would plug it off) every 30-50 minutes. Cooling is fine, temperatures are not going above 45C, PSU should be ok too because I've tested it on different one too. Its not even because of windows - it shutdowns even if leave it in BIOS. Memtest and other stability test were fine, voltage is fine too. I don't really know what is with that...

 

[neo]

Hi, I have issue with my system:

ASUS M2N-E
AMD Dual-Core Athlon A64 X2 3800+
512MB DDR2 667MHz PC5300 CL5 KINGSTON
Leadtek WinFast PX7600GT TDH

FORTRON 400W ATX
ARCTIC Freezer 64 PRO
CoolerMaster Centurion 5

It repeatedly shutdowns (like if you would plug it off) every 30-50 minutes. Cooling is fine, temperatures are not going above 45C, PSU should be ok too because I've tested it on different one too. Its not even because of windows - it shutdowns even if leave it in BIOS. Memtest and other stability test were fine, voltage is fine too. I don't really know what is with that...

I have the same problem ,but under linux with the lastest bios it don't happen,for the moment.
Under winxp it happend random,but with multimedia is more frequently.
I use the lastest drivers for nforce ed GeForce 7600, i made a burn test of memory and cpu but all it's ok.
My system is quite similar :
Amd x64 dual core 4600+
2Gb Ram DDR800(*)(**)
HD Maxtor 320GB
HD Maxtor 250GB
Nvidia 7600
motherboard M2n-e not sli with nforce 570
550W Atx(*)

(*) I don't remeber the producer but its a middle price solution
(**) raccommended by the vendor for my solution

Any one have a good idea?