PC switches off suddenly

[harry smit]

As there are lots of experienced PC users reading this DUC I would like to know if there is somebody who could help me.

Phenomenon:
My PC sometimes shuts down just like that.
I have to remove the power plug for say 20 seconds and it can be switched back on again.

1. Maybe the PSU is somewhat too small?
2. 'Power Good' signal activated?
3. Main board faulty?
It happened after some reboots which were necessary for installing W98 and W2000 with Partition Magic.

Hardware:

PSU:
250W ATX (Inwin Q500 cabinet)

Board:
Gigabyte GA-6BXD, Rev 1.6, 1998 /
Intel 440BX AGPset (I do not know whether it concerns the Seattle version , but one IC contains the codes FW82371EB and SL 37M, 1998 Malaysia)
Bios: AWARD 4.51;
Bus speed: 66 MHz;
IDE: Ultra DMA/33;

OS:
W98SE UK and W2000 SP2 (selectable with Boot Magic upon start up).

RAM:
400 MByte

Processors:
Dual Intel Celeron 400 MHz (one is, how sad, disabled by Windows 98 SE) / L2 Cache per processor: 128 kByte.

Hard Disks:
1. Western Digital WDC AC418000D / 18 GByte / 7200 RPM / EIDE
2. An old Quantum 1.2 GByte / SCSI

SCSI:
Adaptec 2940U2W with BIOS V2.20.0.

CDs:
Plextor Ultraplex and Plexwriter / SCSI

Video:
ASUS 3800M / 32 MByte / TNT2-RIVA / AGP; user setting: 1024 * 768 - 72 Hz.

Audio:
AudioMedia III / BK08276 / upgraded by DigiDesign for Apple Macintosh G4.
Works fine with PT_LE under W98SE and one Celeron 400.

I hope that you are still able to give a possible solution after reading all these details.

Thanks in advance.

Harry

Sorry for posting this for the second time.
The former title 'PSU or something else' was a bad header. [img]images/icons/rolleyes.gif[/img]

[JMS40]

There are many threads along these lines and numerous possible causes... including power supply and ram. Try searching for Spontaneous Reboots.

[tmat1075]

When that happened to me, I was told to turn the video acceleration to "none". and I haven't had a problem since.

[Mark_Knecht]

I vote for Power Supply too small...

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by harry smit:
250W ATX (Inwin Q500 cabinet)
<HR></BLOCKQUOTE>

[Jopry]

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by Mark_Knecht:
I vote for Power Supply too small...

<HR></BLOCKQUOTE>

I agree...check the power supply. Also, what temperature is the cpu running when it shutsdown? Overheating can cause this as well.

[harry smit]

Temperature per CPU: 34 degrees celcius.

[Bastiaan]

do you by any chance have some powerschemes running?????

Bastiaan

[gavinchan]

My vote also goes to the power supply. Check that first since they aren't too expensive. It may be just plain faulty, causing spikes and fluctuations. Or even the power going to the power supply, (from the wall socket) yes, dirty power will effect PC stability.

[harry smit]

Hello Bastiaan,

Thanks for the suggestion but every "Green" thing and screen save bla bla have been disabled. Also in the BIOS.
My opinion is that people should be in control of the PC and not the other way around.

I will start to record the time the PC switches off. Maybe it is mains related. But using a 600 VA / 360 W IMV Victron UPS did
not help either.
According to the read-outs of the UPS the PC consumes about 115 W (@ 230 Vac).
Maybe that 250 W as indicated on the PC is
only for short duration.

Start to think of buying an Enermax 451.

Thanx again.

Harry

[Drastikpup1]

miss matched memory. 400 megs of ram??

memory leak. replace yuor ram with one dim of 512 or 256.