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PC Shutting Off

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Hawkide

Technical User
Joined
Oct 8, 2003
Messages
159
Location
US
I just noticed this yesterday. My computer will run for a few minutes (i'm not sure how long...maybe between 5 and 15 minutes), and then it just powers off instantly (like someone unplugges it).

After it shuts off, it will not start back up. If I wait a few minutes, I can restart it, but then the same problem occurs.

Could something be overheating? Maybe that is why after some wait time I can restart it again.

My PC has one fan on the front, and it is working. I can also feel air being blown out the back from the power supply.

I built this PC about 4 years ago and it has run fine up until yesterday. I am not a computer guru, but I am not a total rookie either...I would truely appreciate any help with troubleshooting this. TIA...Derek
 
Check to make sure that the CPU fan is running while the power is on, and not clogged up with dust. Sounds like overheating.
 
Sounds like an overheating problem. Time to open up and gently loosen the dust around the CPU and Fan (use a small soft brush) and then blow away. Check that the heatsink/fan is still attached firmly and then switch on to check that the fan is spinning freely.

It is also possible that the power supply fan has seized up too: but that usually manifests itself with an unpleasant burning smell!

Regards: tf1
 
I was completely stumped when something like this happened to be a couple months back. I had just added a new DVD burner, closed the case back up, and it started doing this very thing. I eventually discovered that my CPU fan was being obstructed by a ribbon cable, and some internal monitor automatically shut the PC down to prevent damage. Run it with your case open and make sure all your fans are spinning up.

Despite the above scenario, spontanious shutdowns almost always have 2 causes: overheating or an faulty/overloaded PS.
 
Hawkide,
I noticed your post and found this info, it comes from

(middle of the page or so)

...Your computer shuts down by itself
The hacker can cause your computer to shutdown if you are infected by an Internet Trojan.


Your computer shuts down and powers off by itself
Once infected, the hacker can make your computer turn itself off.
...
 
A newer Intel should automatically throttle-down if it senses overheating. I've seen some good videos on tomshardware.com of AMD's burning up. (running with no heatsink is not recommended, hehe)

let us know what you find out.
 
Hawkide
Definately check the CPU heatsink and fan for dust build up and free fan movement, this is a routine maintenance task that all users should carry out at least twice a year.
These symptoms could also indicate an overheating/failing power supply unit.

Martin


We like members to GIVE and not just TAKE.
Participate and help others.
 
adding to some very good suggestions above, maybe your psu is not up to the task of having another hardware installed. adding more power is an option. try borrowing a good 500w (or more) psu from a friend, install it to your pc and see if the problem go away.

hope this helps. peace! [peace]

kilroy [trooper]
philippines

"Illegitimis non carborundum!"
 
Well, I have not added any new hardware, so I don't think the Power Supply was overburdened (it has been running fine for 4 years)

When I got home on Wednesday, my wife informed me that the PC had "randomly" shutdown on her (I had forgotten to tell her there was a problem). I blew out the dust inside the case, and now it wont turn on at all ( I don't think that blowing out hthe dust has anything to do with it).

Anyway, when I press the power button nothing happens. I don't even hear the power supply kick in. Is this an indication that the power supply is dead? I am guessing that if the problem was the CPU that I would at least hear the powersupply fan start when I press the power button ( unless maybe the power connection from my motherboard to the powersupply has taken a dump).

Any ideas will be greatly appreciated...
 
It is looking increasingly likely the PSU has got for burton, the shutting down possibly an early warning of this imminent failure.
I would try pulling off and examining the main power connector, just in case it has a poor contact (burnt pins)
otherwise try and borrow a replacement PSU if you can before shelling out the $$$$$'s
Martin


We like members to GIVE and not just TAKE.
Participate and help others.
 
It is looking increasingly likely the PSU has got for burton, the shutting down possibly an early warning of this imminent failure.
I would try pulling off and examining the main power connector, just in case it has a poor contact (burnt pins)
otherwise try and borrow a replacement PSU if you can before shelling out the $$$$$'s
Note* quality Antec/Enermax/Zalman/CWT/Chieftech/FSP/Sparkle etc etc perhaps something 400watts plus for future proofing.
Martin


We like members to GIVE and not just TAKE.
Participate and help others.
 
Sorry!
And of course the obvious loose wall socket/wires/fuses and power cable to the PSU.
Martin

We like members to GIVE and not just TAKE.
Participate and help others.
 
Well sounds like a dead Mobo, or Processor to me. There is a way to check your PSU by taking a piece of lets say 10 gauge wire and attaching it to the ATX connector to simulate the mobo connection, turning on. Its a green wire in the middle of the ATX connector. Run wire from that connection, right next to it, left of the first connection is a black ground, connect the other end of the wire to that connection and turn on the PSU. If the fan spins and it powers up its not the PSU.

Also find the jumper to clear CMOS. When clearing CMOS make sure the power cord is not connected to the PC. I doubt that this is it, but on certain newer AMD boards there are settings in the BIOS that will power down the system when it reaches a certain temp threshold. Also there are software programs that will do the same thing inside Windows. Not sure what you got there (how old? what processor, Mobo?...)But if the PSU works then try taking out your processor and trying it in another COMPATIBLE machine to eliminate that component. Also try stripping the machine down to the basics just Video Card, Hard Drive, Memory and running it that way for an hour. Video card have a fan on it? Clean it out and make sure its functioning.


Thats all I can think of off the tope of my head,
Hope this helps.
 
I'll try some troubleshooting this weekend (but may not be able to repost until Monday when I return to work - since my only PC at home is the one in question).

My system has an ASUS CUSL2 motherboard with a Pentium III 866 MHz. I built the system about 4 - 5 years ago and have not made any hardware changes (except for adding a DVD player 3 years ago). Not sure if the video card has a fan (I believe it is a GForce 2 MX - don't remember the manufacturer, and since I'm at work I can't check now).

I really appreciate the help guys...
 
I'm jumping in here with a very similar problem and hoping a solution will be offered for Hawkide & me. Last month I bought one of those free (after rebates) Soyo P4I865PE Plus V.2 motherboard, added an Antec True 430W PSU, memory and 2.4ghz P$ (Prescott). After a couple of weeks of flawless running I found I couldn't wake it up from sleep mode and the powerswitch wouldn't work. Turned off and on,the switch on the PSU; still dead. However, unplugging and replugging power cord at PSU brought it back to life. This has worked on those occasions that the system wouldn't awaken from hibernation for the past couple of weeks. Until this evening. I am suspecting the MB (perhaps the reason it was so cheap :-)) The PSU checks ok, but the active diode on the MB doesn't show life. Anyone beside Hawkide and me have encountered this?

 
How long do you leave this in Hibernate? The reason I ask is that I had a similar but intermittant problem. I eventually reaslised that it wouldn't wake up when it had hibernated for several hours. This led to me discovering that in hibernate, the motherboard wasn't shutting down the CPU and the CPU was eventually overheating even though off load.

I temporarily resolved this by disabling the CPU fan from stopping during hibernate. Eventually, I got a BIOS update for the motherboard and that resolved the problem. The CPU should slow down to about 1Hz in hibernate - just sufficient to note wake up activity.


Regards: tf1
 
Thanks for the reply TF1, it's possible but unlikely even though it's asleep for 8 to 10 hrs. I keep my case unbuttoned and the ambient temp is between 70 & 74 deg. My CPU temp stays below 40 C under full load. For added info, I had it hang a several times while operating also. I've checked this forum for others with this experience and no-one seems to have a definitive answer in the past. The normal troubleshooting technique seems to be to remove and test the mb out of the case. Which I'll be doing shortly, however, I don't suspect a short. Since it's new it will have to come out to RMA anyway.

I'm still hoping someone has had experience with this mobo (SY-P4I865PE Plus Dragon 2 V1.0) and can relate good or bad experience. Or better yet, a "positive" way to diagnose this type of problem. :-)
 
Follow Up. I discovered my problem. I had damaged the lans when I installed the mobo. It doesn't help to scratch them on the mounting posts. A word of caution to all... it's an expensive error...;-)
 
Well, I borrowed a spare power supply from a neighbor and the motherboard sprang to life. I purchased a new power supply today, and I am up and running again. I am so happy the fix was only 40 bucks. Thanks for your help guys... (-:
 
I would imagine the same suggested fixes also apply to laptops, am I correct?
Thanx

 
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