Suddenly, spontaneous shutdowns

[lenjack]

My system has been running perfectly for 2 months. Recently, with no changes made, it will shut down with no warning. It often does this on a cold start...it will start up, fans run, boot up screens appear, and within about 10 second from powering on, it will shut down. Sometimes it will start properly and shut down in 5 to 10 minutes. At other times, it will do this after an hour or so. It is unpredictable. I have been checking voltages and temps every few minutes, and they are normal (temps 44 to 46). I want to stress that nothing has been changed in the system for over 3 months, and all ran well until this.


Specs:

W98 all critical updates
Athlon Tbird 1333 @ 1506
Arctic Silver
Swfttech MC462A
Abit KR7a board bios 6n
256 M Crucial pc2100 DDR
Radeon 32m ddr video
Santa Cruz Sound
Lucent winmodem
Maxtor 7200 30.7G HD
Maxtor 5400 20G HD for backup only using DriveCopy4
Sony 52x CDrom
Plextor 16x10x40 cdr, cdrw
floppy
2 fan bay cooler in top bay
Enermax 350w PS (5v stays at 4.97 to 4.92)
Enermax 7237 case
120mm lower front case fan (difficult mod)
80mm fan on exhaust beow PS
bios using most aggresive settings and timings, and cpu at 9.5 x 158

Althogh these settings are aggressive, they have caused no problems.

Any ideas?

Thanks in advance.

 

[Mavrick007]

Hmmm it could be a windows problem, and if so a reinstall should help, or it could be your psu is failing. Even though it is holding close to 5V, it might still be failing. I would check it out with a different psu and see if that helps. Make sure it's a good quality with enough juice coming out cause you have quite a bit of stuff in your machine(another 350+ quality psu should be sufficient).

 

[samgau]

There is a couple things you might want to try... boot up from a cd/floppy and see if it still does the shutdown thing... if it does then its not your OS... if it doesnt then you could try booting from your backup drive (disconnect the primary) and see if it happens again... you could also try to pull all your cards and devices except for the video and boot from a floppy and see if it still happens... you see where im going?
more conservative setting on your mobo is also something to try...

 

[Mem]

I had this problem( spontaneous shutdowns) with a 9 month old AMD approved PSU that had gone faulty,I replaced it with a new PSU(Enermax) and it solved the problem so I would try a new PSU first.

Btw my PSU voltages seemed ok before the random shutdown as well.

I notice your CPU is overclocked do you get the same problem at default CPU speed?

 

[lenjack]

Mem...Yes, same problem at default. A windows reinstall didn't help. I would suspect the ps too, even though it's a high quality supply. Any recommendations on a new ps. Should I try another Enermax? I don't want to go pc power and cooling because of the expense. I know the Antec ps is highly regarded, but the Enermax is supposed to be better. It may not be the ps at all.

 

[lenjack]

^