[Okta Webinar] Learn how to a build a cloud-first strategyRegister Now

x
?
Solved

PC power off suddenly

Posted on 2011-10-22
18
Medium Priority
?
362 Views
Last Modified: 2012-06-27
As above, when I switch on my PC for the first time of the day, it can last for about 10minutes or longer. However, once it encountered the first power off and when I try to switch on immediately, it may not last till a complete boot to windows.

I suspected the PSU so I used a multi meter to test on the voltage. Everything on the 24pin ATX connector seems to be within the tolerance level of voltage.

What other test should I do?

I am now observing the "PC health status" from BIOS. (First boot of the day, probably temperature still cool)
CPU temperature is now at 46 degree celcius.

PSU: CORSAIR VX550W
MOBO: GIGABYTE EP45-UD3P
CPU: INTEL CORE2DUO E8400
0
Comment
Question by:humansg
  • 5
  • 5
  • 2
  • +5
18 Comments
 
LVL 9

Expert Comment

by:vaderj
ID: 37013151
For 1, its tough to measure ampres on a psu.  2, that really sounds like a cpu cooling issue. 46 sounds a tad high at idle .... Put some presure on it and its probably popping up quite high.  I got a "sample" of thermal goo from dow chem. a while back, they sent me a kilo!  But where I'm going is that I have replaced the thermal paste on all of my cpus over the past year and watched the average temp drop about 10c each time. Ill post the specific formula model when I get home. But where I'm going is that when you goop up your cpu, you dont want to over due it, but you need to make sure that you have a consistent solid layer over the entire  thermal displacement surface of the cpu.  I had this same issue with an old prescot cpu awhile back which prompted me to regoo.
0
 
LVL 30

Assisted Solution

by:Dr. Klahn
Dr. Klahn earned 300 total points
ID: 37013160
The symptoms described indicate a thermal problem in the system; that is, the system boots the first time, runs a while, then shuts off, and thereafter shuts off immediately.

Monitoring the system temperature from the BIOS is not diagnostic for these problems.  The BIOS reported temperature is for a single point in the system, usually the CPU, without load and not running anything.  Suggest you download a Windows thermal monitor such as RealTemp or CoreTemp that will report the temperatures while the system is running.

Core2 Duo CPUs need good heatsink/fan combos.  The Intel supplied versions should be considered a bare minimum, not the standard.  Any slippage of the mating surface or slowdown of the fan can result in impaired cooling.
0
 
LVL 3

Expert Comment

by:Praveen Valluri
ID: 37013176
If there is an option APIC Enabled in BIOS= Disable the same.
Replace the BIOS battery and check.
0
VIDEO: THE CONCERTO CLOUD FOR HEALTHCARE

Modern healthcare requires a modern cloud. View this brief video to understand how the Concerto Cloud for Healthcare can help your organization.

 
LVL 1

Expert Comment

by:Crackx2008_INFOTEC
ID: 37013195
I think is a CPU temp problem, or bios shut down temp too low, could be also low rpm in fan or low rpm in bios..

Good Luck!
0
 
LVL 14

Accepted Solution

by:
Rob Miners earned 800 total points
ID: 37013232
Faulty Fans, Dust and Grime build up on the Heatsink, all contribute to restricting air flow.

Remove the Power cord from the PSU to discharge the Capacitors in the Power Supply. Then press the Power button for 10 seconds to discharge the Capacitors on the Motherboard.

Remove the cover from the PC case. Ground yourself by placing the back of your hand on the Power Supply Unit and not moving your feet. By not taking this precaution it is possible that you could inadvertantly cause damage to the PC from an electrostatic discharge.

If you can, give the inside of the case a blowout with compressed air. When blowing air through the fans make sure that you physically stop them from spinning, as they may generate power and blow something up.

With the Motherboard power connector disconnected to the CPU Fan, give the fan a spin, if the fan spins freely it's probably OK. If there is any resistance it should be replaced.

Then remove the Heatsink, giving it a thorough clean with a cotton cloth and reseat the CPU applying new CPU grease. You only need enough grease to make a seal between the Heatsink and CPU.
0
 

Author Comment

by:humansg
ID: 37013275
Ok this is what I have done so far.

When I managed to get onto desktop, I downloaded Prime95. Upon immediately starting the test which suppose to generate most heat and use most power consumption, the PC power cuts itself off.
Then when I tried to switch it on, it will switch on for say 3 seconds then power down again... and power on for 3 seconds (automatically) and power off again... I have to manually switch off the PSU for sometimes before able to turn on for it to POST. (Seems like what rrjmin0 have said about discharging capacitors).

Then I went into BIOS and it is able to stay in BIOS for at least an hour before I shut it down myself.

I will try cleaning up the CPU fan and resitting the heatsink as suggested. Do I need to reapply the thermal compound?
0
 
LVL 9

Assisted Solution

by:vaderj
vaderj earned 300 total points
ID: 37013288
BTW, the Dow thermal paste that is the best I have ever seen in 15+ years of building and overclocking PC's is "Dow Corning TC-5022"
I got it by telling them (when I was) an engineering student for the State University I was attending at the time.  I would say to eliminate all doubt, to reapply the thermal paste. Its cheaper to put $.25 worth of goo on your CPU than replace you CPU
0
 
LVL 14

Expert Comment

by:Rob Miners
ID: 37013306
Do I need to reapply the thermal compound?  Yes you do have to use new thermal compound. Aka "grease" as it aids in thermal dissipation via the heat sink.
0
 
LVL 93

Assisted Solution

by:nobus
nobus earned 300 total points
ID: 37013685
to verify if it is a temperature problem, install speedfan to monitor the temps : http://www.almico.com/speedfan.php

also - test if it cuts off when you boot from a live cd, or in safe mode
post results..
0
 
LVL 5

Assisted Solution

by:andrewmcc
andrewmcc earned 300 total points
ID: 37015078
Hi
Simple test, make sure the mainboard is not shorting anything out.
You don't say if this is a new pc or old pc.

Also, if you have kids, check the status of the capacitors on the mainboard.
You should see if the tops are flat and showing clean and tidy.

Coming to "kids", check the top of the capacitors - simple test.
(Like baby food or jars of jam - the tops of the food or jars let you apply pressure and you can tell if they have been opened?)
If you have discoloured or distorted capacitors - you may still have power going through the psu, but the mainboard might be blown.
Also, what kind of graphics card do you have?
If you have anything like a gaming or cad card - check the capacitors on the graphics card as well.
They can overheat, pass excess heat and overload if you have had any power cuts lately.

If capacitors have blown, it is not worth replacing them.
Usually you need a new mainboard, check memory as well.

Typically the capacitors blow around the power/psu connector to the main board, cpu and graphics card.

0
 

Author Comment

by:humansg
ID: 37024434
Dear all experts!

I have read all your comments and I think it may be a temperature problem as what all have suspected. I just reapplied some of the thermal compound and is doing test using Prime95.

Not sure if I applied it the right way. But I did not finish the whole 1g tube. I followed this video here http://www.youtube.com/watch?v=fRRWbQUqW1Y
putting the thermal compound in a "line" (Please let me know if I applied it the wrong way)

So far so good. (Better than previously when I start the test, it just power cut immediately)
Max temperature as seen from Real Temp is 70 degree celcius. Hovering at 68-69 degree celcius under full load. Running for more than 20minutes now.
Can anyone comment on the temperature readings? If it's too high.. using the stock cooler though..

Capacitors are all fine. No signs of bloating!
0
 
LVL 93

Expert Comment

by:nobus
ID: 37024915
i always use a minimal drop only - then smear it out; it is not intended to make a layer, only to fill air crevasses

>>  I think it may be a temperature problem  <<  ok - did you use speedfan?  because that will show it clearly

70°  is very near the top limit, see  : http://download.intel.com/design/intarch/core2duo/316676.pdf
0
 

Author Comment

by:humansg
ID: 37024947
I am using Core Temp 1.0 to view my temperature readings now. Will speedfan be better?

Just now after running about >30mins of Prime95 stress test, I stopped and continue my normal work. However, it power cuts one time! Now I am on normal load, so far so good now. Not sure if the CPU fan is dying on me that's why giving me such problem. lol..
0
 
LVL 93

Expert Comment

by:nobus
ID: 37025232
probably not  - the cpu fan?  you should hear that no?
0
 

Author Closing Comment

by:humansg
ID: 37046496
Heat problem
0
 
LVL 93

Expert Comment

by:nobus
ID: 37049052
so what was the cure?
0
 

Author Comment

by:humansg
ID: 37049433
It is most probably CPU heat problem.

I am closing this thread as it have been labelled inactive and I will get a new CPU fan when I am free and post a new thread if there is still a problem.
0
 
LVL 93

Expert Comment

by:nobus
ID: 37049682
tx for feedback
0

Featured Post

A Cyber Security RX to Protect Your Organization

Join us on December 13th for a webinar to learn how medical providers can defend against malware with a cyber security "Rx" that supports a healthy technology adoption plan for every healthcare organization.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

I use more than 1 computer in my office for various reasons. Multiple keyboards and mice take up more than just extra space, they make working a little more complicated. Using one mouse and keyboard for all of my computers makes life easier. This co…
New style of hardware planning for Microsoft Exchange server.
Please read the paragraph below before following the instructions in the video — there are important caveats in the paragraph that I did not mention in the video. If your PaperPort 12 or PaperPort 14 is failing to start, or crashing, or hanging, …
Screencast - Getting to Know the Pipeline
Suggested Courses

872 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question