PC shuts down - Voltage issues??

[Mermer]

Hi there,

Since 2 adys my PC randomly/suddenly shuts down. I think my mobo prevents itself from being damaged..
With HMonitor i could read out some info:
CPU temp: normal
Mobo temp: normal
HDD temp: normal
Fan speeds: normal
Voltages: all normal :eek: EXCEPT the -12v is @ -14,84v!! :eek:

Furter information:
CPU: P4 3,0 GHz HT
Mobo: Asus P4C800 Deluxe
Video: Point of View FX5900XT @ 12% overclock
HDD: 160GB and 80GB
Memory: 1024 MB noname brand
Running WinXP Pro

Does anyone have an idea what could cause the strange voltages?
Thanks!

Merijn (NL)

[khilladi]

what exactly is the cpu temp? and that is the -12v right? speedfan (temp monitoring program) tells me -9.40 on a regular basis.... what's the vcore on that p4? no oc?

[Mermer]

CPU 52,0C
HDD 35,0 C
mobo 33,0 C

+12v @ 11,49v
-12v @ -14,84v
+5v @ 5,06v
Core @ 1,41v
i/o @ 3,31v
Aux @ 3,18v <-- this appears red (dangerous) too :(

[therealwesty]

Welcome to PCStats Mermer!

The negative voltage rails are pretty much for legacy support, they are used as referrence voltages for older devices. They aught not effect your system too much, though nearly 15v is pretty drastic. What is the brand and wattage of your power supply?

Some testing I might do... Grab a Windows based temperature monitor program, Asus Probe is available on the mobo CD or from the Asus site. Grab a stress testing application like SiSoft Sandra or Prime95 (http://www.mersenne.org/freesoft.htm). Run a high-stress or burn in test on the system while monitoring the temperatures and voltages under load. If the temperatures climb out of control that you are obviously going to need to improve your cooler. If the voltage fluctuate heavily than you might consider a new PSU.

PSU can be as easily overlooked component yet it is crucial in the reliability of your system. A high quality PSU will cost a little more than a generic one but the extra price is worth it. Lower cost PSUs usually can't sustain their advertised wattage rating at all, it is for a momentary peak and that's it. A high quality PSU can operate at or near its advertised wattage when need for longer periods of time. Higher quality PSUs also have much better fault protection, so if the PSU does quit there is much better chance it will not kill your motherboard or videocard. Enermax is my #1 choice but Antec and OCZ are also reliable favorites.

[Mermer]

Thanks! I'll try the stress tests!
BTW: My PSU is a Nexus 400W (the one that comes withe the Nexus Breeze case)
I'll subit the test results in an hour or so.
Thanks again for the quick reply! :)

Merijn

[Mermer]

Hmmm... stress-tests are running now, and the CPU temp is around 67C and 68C. The Core voltage drops to 1,33v; the rest stays the same.
The 12v is @ 11,55v and the -12v is still @ 14,84 :confused:
Am I overlooking something?
Any other suggestions?

Thanx,
Merijn

[PCgeek]

Maybe its driver issues, or another piece of hardware might be going. Check the motherboard for any bulging capacitors, happens pretty often.

[khilladi]

what is it that you do prior to the pc shutting down? gaming? and run prime for about 2-5 hours to see your max load temp

[Mermer]

The last things were file transfers (4+GB) in my LAN.
I'll let Prime95 run tonight and check the logs tomorrow.
Driver issues won't be the problem (I hope) cause I still use the old and stable(!) drivers; I've got the same hardware config for 3 months now, with no problems...

I'll get back on this tomorrow-evening.

Merijn

[Zefram]

take a powerful desk fan, open up your side panel and let the wind blow to your mobo.......................
My friend 3.2Ghz P4 acted up, random error, crashes and when i do the aforementioned step, the system works fine.............

Sometimes its maybe the south or northbridge chip that get too hot and well, practically corrupted the data and stuff :D

[blueice]

Master Zefram, Dr. Goodwrench, that is a great idea. Who said that positive pressure is of no valve, my friend. :D

[therealwesty]

When the PC is on you could try to touch the various heat sinks on the CPU, NB etc to see if any of them feel extraordinarily warm. Your CPU temperature reading seems allright for a P4, so I am thinking one of the other components could be overheating. I had an Asus A7N8X Deluxe motherboard and the NB heatsink was not properly mounted. As a result the NB (memory controller) was overheating and causing a lot of unpredictable problems and crashes.

[Mermer]

One long night testing.. no crashes. But now, if i play world of warcraft, it crashes after 15 minutes, and with dvd-decripter it crashes after 10-20 minutes :(

I'll try the heatsinks tonight, hoping i can find the solution for my problems.

Thanks again for all your help!

Merijn

[Mermer]

Problem solved!
Complete windows reinstall and no chrashes since. My -12v is still @ -14,9v but it seems to work fine now. Hope it stays this way :)
Thanx again for all your help!!

Merijn

[therealwesty]

After reading post #13 I was about to suggest it must be something to do with the drivers or some deep down software conflict. After reading post #14 it cetainly looks like that was the case.

Glad you got it straigtened out!

[Mermer]

I'm glad too.. "bugs" give me the creeps :)