# PC randomly shut downs



## siiimmm (Apr 30, 2012)

*Hey guys...

Well, I was playing Borderlands when suddenly the PC shut down completely. After that, I tried start it up again (with power button obviously XD) and nothing happens, it was like the power supply's cable wasnt pluged. After waiting like 5 minutes it started up, weird I guess... my guess is a component overheated and it wasnt starting up becase it was waiting for those or that component to cooling up.

Any ideas?

Thanks in advance!*


----------



## etaf (Dec 28, 2008)

does sound like a heating / power supply issue 
what type of PC is it - desktop / laptop 

you should clean out all the dust -


----------



## siiimmm (Apr 30, 2012)

Ah damn it, I always forget system specs.

Well, it is a desktop, and the PSU is a Cooler Master Silent Pro 700 watts.

Rest is:
- Intel i5 750
- MOBO Gigabyte H55M-USB3
- 4 GB ram 1333
- EVGA GTX 550 Ti.

Recently I cleaned up all the dust, but yeah, maybe it could be a overheating issue with the PSU, since I live in a kind of hot place. But at the end, Im not the expert.

Thanks for the answer!


----------



## JimE (Apr 16, 2009)

Shutdowns are typically a hardware fault. Most likely the power supply or motherboard.


----------



## siiimmm (Apr 30, 2012)

Well it happened again. PC did shut down, pressing power button didnt work, nothing was happening. Tried the PSU back switch, turned off and on, still, nothing happening by pressing power button. Unpluged cable from PSU for about 10-15 seconds and then plugged it back, still nothing. After waiting about 10-15, PC turned on by pressing power button. Kind of weird.

This appeared when PC booted up: http://i.imgur.com/D2hea.jpg

However, only pressed F1 to continue to boot and everything was back to normal.

Any ideas?

It is getting really frustrating.

Thanks in advance guys!


----------



## etaf (Dec 28, 2008)

how old is the PC 

have a look at the event viewer and see if anything is listed at the time it shuts down
Start>control panel>administrator tools>event viewer


----------



## siiimmm (Apr 30, 2012)

It is 1 year and 4 months old, however, the PSU is about 8 months old.

There is a Critical Kernel-Power event, which happened at the time PC shut down.


----------



## siiimmm (Apr 30, 2012)

Sorry for double post, I cant edit previous post.

So, I ran Memtest86 for 5 hours, but everything seems normal, guess we can discard RAM?

http://i.imgur.com/gBdjI.jpg

I just changed both GPUs and CPUs thermal compound, will see how it goes.


----------



## Wrench97 (May 10, 2008)

Use Hardware Monitor  to monitor the temps and voltages, you can run HWM in the background while doing something intense like gaming or a virus scan, Alt+Tab back to the HWM screen expand all the trees, use the Win7 Snipping tool to take a screen shot of the window then using the Advanced Reply box there is a paperclip button at the top to attach the image of the HWM window


----------



## JimE (Apr 16, 2009)

Was the power supply an upgrade or a replacement? If a replacement, why was it replaced?


----------



## siiimmm (Apr 30, 2012)

It was an upgrade, I had a sh*tty one xD.

By the way, just happened again, had to wait like 20 minutes before start up lol.

I had a program to auto-screenshot every 3 minutes, so we can see temps before shutdown, everytime seems normal tho, this screenshit was the last before shutdown:

http://i.imgur.com/iEpUP.jpg

Also, in startup, this came out:

http://i.imgur.com/zdSvm.jpg

It rebooted like 5 times before normal boot.

Ahh man, this is really annoying now, cant play without shutdowns, lol.

Also, this has not happened when mini split is on. So, it could means is a overheat issue, BUT temps seems normal so far :/. Something I noticed too, the HDD was kind of hot, can a overheating HDD causes a system shutdown, then wait to cooling up to startup?, or it is a MOBO issue?

Something weird I noticed, the system time will stop after shutdown, what I mean is, for example, if the time is 15:00 at the moment the system shut down, then I wait 20 minutes to startup, the system time will be still 15:00.

Thats all I have for now >.<


----------



## JimE (Apr 16, 2009)

The error on startup appears to be BIOS related. 

If it were simply a boot issue, I'd suspect the BIOS battery or maybe a corrupt BIOS. As you are also having the shutdown issue, I'd suspect a motherboard fault.


----------



## siiimmm (Apr 30, 2012)

Could be also a faulty temp sensor in the mobo?, because, as I mentioned before, it only happens under load, so, when the mini split is on it does not happen, and considering I live in a kind of hot place... now it is 34°C, and my PC only have 2 fans , system fan and CPU fan, and cant do cable management because of the case (Cooler Master Elite 335)...

Next time it happens I will try to do the paperclip "trick" on the PSU to see if it gets on, I guess thats the only way to confirm that the MOBO is the issue.

Also, should I do a BIOS recovery?, my MOBO is this one:

GIGABYTE - Motherboard - Socket 1156 - GA-H55M-USB3 (rev. 2.0)

Thanks for all the help, really appreciate it.


----------



## JimE (Apr 16, 2009)

IF it was temp related (ie: overheating), such as with the cpu, you would get an audible alarm as it shuts down. And typically the only temp monitored is the cpu temp, which from your monitoring is not overheating. At least in my experience. In any case, a faulty sensor would fall into the "motherboard fault" category.

A recovery of BIOS update likely wouldn't hurt. Luckily that board has "dual bios", because if it shuts down during the update it will be corrupted.


----------



## siiimmm (Apr 30, 2012)

Hey, me again, I tried to reproduce the issue, and, success, lol.

This time I tried the paper clip trick on the PSU to discard a PSU issue. The PSU did indeed turned on with the paper clip trick after the shutdown. I even left the CD-ROM connecteds to try, and yeah, it was working. So yeah, PSU issue discarded?.

Atfer the trick, reconnected to the MOBO again, and it wasnt turning on. So, I believe now it is a MOBO issue, but, what MOBO issue exactly?, I dont know :/.


----------



## Wrench97 (May 10, 2008)

That does not eliminate the PSU, you have check the PWR_OK signal with a voltmeter as well as the PWR_On lead> http://www.techsupportforum.com/forums/f210/test-your-power-supply-with-a-multi-meter-151526.html


----------



## siiimmm (Apr 30, 2012)

Ah, well, sadly I dont have a multi meter.

Also, considering the PSU wont turn on when connected to the mobo, BUT it will just with the paper clip trick, that cant be related to a MOBO issue?


----------



## Wrench97 (May 10, 2008)

Maybe, maybe not.


----------



## siiimmm (Apr 30, 2012)

How can I confirm is a MOBO related issue?, maybe after doing the multi meter tests?


----------



## Wrench97 (May 10, 2008)

The multi meter will tell you if the power switch connection through the motherboard is triggering the Pwr_on pin to the PSU if it is and PSU is not turning on the MB is ok. if not eliminate the switch and wiring by jumping the front panel pins on the board while testing.

Have you checked the capacitors for domed tops, leakage or missing cans?
>> Badcaps.net - How To Identify


----------



## siiimmm (Apr 30, 2012)

Still couldnt get a multimeter, but I manage to get a PSU voltage tester.

Here is the pic:

http://i.imgur.com/I2Ncn.jpg

The lights on red circle are the only that didnt turn on. The 8 and 6 pin seems to be working correctly tho, since it only says to check for +12v. Now, the 24 pin, the only that didnt turn was the -5V, could be that an issue?. Sadly I dont know much about voltages and that stuff, so I coulndt tell. Hope you guys can help me again!

Also, yes, I checked the capacitors, everything looks fine with them.

Thanks in advance!


----------



## Wrench97 (May 10, 2008)

-5v is normal it was removed from the ATX spec after version1 about 10 years ago, the 2 on the left side are not lit since a floppy drive plug is not plugged into it.

Unfortunately that type of tester tells you nothing about voltages under load or the PWR_OK, PWR_On circuits when the issue is actually happening.


----------



## siiimmm (Apr 30, 2012)

So, should I try with a multimeter test?

Also, whatever the issue is with the PC, it is kind of weird. First, the shutdowns will only happens when the mini split air conditioner is off, "suggesting" it is an overheating issue, since I live in a "kind of hot" place, but it does not seems to be an overheat issue, since temps are always in normal ranges. Plus it wont let me turn on the computer again until it cools up.

Thanks for all the replies by the way, really appreciate all the help.


----------



## Wrench97 (May 10, 2008)

What is a mini split air conditioner?
If it's another device that plugs into the wall are they in the same outlet or circuit in the house?


----------



## siiimmm (Apr 30, 2012)

Hmm, this:

https://www.google.com.mx/search?hl...urce=og&sa=N&tab=wi&ei=NnipT5TsDYWdgwfFmIGdCA

Those things you turn on when the weather is hot. :]


----------



## Wrench97 (May 10, 2008)

Ok so it's a AC unit that's wired into the house and not one that plugs into the electrical outlet the PC is on like a window unit(Besides I read your post incorrectly as you did say it happens when it's off not when it's on) 

Certainly sounds like a heat issue, will probably take a voltmeter hooked up to a spare 4 pin molex(IDE drive power plug) while the PC is up and running to see if the voltage drops off when it's hot.


----------



## siiimmm (Apr 30, 2012)

Wrench97 said:


> (Besides I read your post incorrectly as you did say it happens when it's off not when it's on)


Well yeah, it has been happening ONLY when the AC unit is off so far. And yeah, the characteristics of the issue "suggest" is a overheating issue, but as I mentioned before, the temps looks fine before a shutdown, which is weird.

So, hopefully I can get a multimeter as soon as possible to do the molex test.

In the meantime, any other tests I could do?

Thanks again.


----------



## Wrench97 (May 10, 2008)

Do you feel the fan in the power supply running(blowing air out the back)?


----------



## siiimmm (Apr 30, 2012)

Yeah, the PSU's fans seem to be working perfectly, it also blows air out the back, and I saw it working when I did the paperclip trick. When shutdowns occurs, I touch the PSU to see it is overheated, and nope, it is normal and not even hot.

Both, system and CPU's fans are working, GPU's fan as well.

What I have noticed lately, is that the HDD is kind of hot.


----------



## Wrench97 (May 10, 2008)

Use Hardware Monitor  to get a look at the hard drive temps.


----------



## siiimmm (Apr 30, 2012)

Temps while just browsing the internetz:

http://i.imgur.com/cknve.jpg

Everything seems normal so far.


----------



## Wrench97 (May 10, 2008)

Other then the voltage reading for the 12v yes.


----------



## siiimmm (Apr 30, 2012)

Care to explain? :c, please.


----------



## Wrench97 (May 10, 2008)

The spec is +/-5%, so for the 12v 11.4v to 12.6v, the closer to 12v the better.
Sorry I thought we covered this but looking back I see not, check in the Bios on the PC or hardware health page to see what it lists for the voltage readings. This is another instance the volt meter would tell for sure.


----------



## siiimmm (Apr 30, 2012)

Ah I see.

Alright, I'll take a look at the BIOS hardware health and get back to you as soon as possible.

Thanks again.


----------



## siiimmm (Apr 30, 2012)

Alright, done, here are the screenshots from the BIOS:

PC Health Status:

http://i.imgur.com/Xd2Uk.jpg

Motherboard Voltage Control:

imgur: the simple image sharer

Power Management:

http://i.imgur.com/0etDi.jpg

I know you only asked for health status, but hopefully the other ones can help.


----------



## Wrench97 (May 10, 2008)

12.429v leads me to believe the HWM reading is correct.
What Brand and Model Supply are you running?
If it has over current protection then it may be shutting itself down when it gets over 12.6v as it should.


----------



## siiimmm (Apr 30, 2012)

The PSU is a Cooler Master Silent Pro 700w. It is about 9 months old.

It seems it have OVP, along with many other protections.


----------



## siiimmm (Apr 30, 2012)

Also, is that OCCT software trustworthy?, should I do a PSU test with it?

Home


----------



## Wrench97 (May 10, 2008)

It's worth a shot but all it does is load up the system there is no way use software to test a PSU.

OVP/OCP simply shuts off the PSU if the voltage gets over the threshold.

I would contact Coolermaster for a Warranty RMA.


----------



## siiimmm (Apr 30, 2012)

Wait, but it is really the PSU the issue here?, I mean, yeah, it could be the +12v stuff on the PSU, because it sometimes reach 12.61v, and it doesnt shutdown. For example, now it is looping between 12.48 and 12.54v, but, if I did understand correctly, those values are in the accepted range of 5%. 

Also, last time a shutdown ocurred (like 5 days ago), the PC (and PSU) wasnt turning on when the PSU was connected to the MOBO, BUT the PSU did turn on with the paperclip trick.

And also, dont get me wrong, I know what a RMA is, but I have never filled one. Do I have to send the faulty PSU (if thats the case) to Cooler Master, so they can send a new one?.


----------



## Wrench97 (May 10, 2008)

> And also, dont get me wrong, I know what a RMA is, but I have never filled one. Do I have to send the faulty PSU (if thats the case) to Cooler Master, so they can send a new one?.


Unless the store you bought it from will exchange yes you would have to ship it to Coolermaster.



> Also, last time a shutdown ocurred (like 5 days ago), the PC (and PSU) wasnt turning on when the PSU was connected to the MOBO, BUT the PSU did turn on with the paperclip trick.


The OC protection would have reset upon unplugging,



> Wait, but it is really the PSU the issue here?, I mean, yeah, it could be the +12v stuff on the PSU, because it sometimes reach 12.61v, and it doesnt shutdown. For example, now it is looping between 12.48 and 12.54v, but, if I did understand correctly, those values are in the accepted range of 5%.


If it shuts down at 12.62v we will not know from the software.


----------



## siiimmm (Apr 30, 2012)

FML, it happened again when I tried to game :/.

I know I'm beeing very very repetitite about this issue, but something I cant still understand... as I mentioned before, after a shutdown, I tried to turn on the computer but nothing was happening, after that I tried the PSU paperclip trick and in indeed turned on, after that paperclip trick, I pluged the PSU back again to the MOBO and again it didnt turn on. Im mentioned this because you mentioned that PSU did turn because of the OC protection beeing resetted upon unplugging, and the thing I cant undersatand, why the PC wasnt turning on when I pluged the PSU back to the mobo after the paper clip.

Also, something I didnt mention before, for example, the shutdown happened aprox at 4:20 PM. When I finally could turn on the PC again (had to wait something like 25 minutes), the time was the same. Can this suggest algo a MOBO issue?

Also, in the Windows event viewer, there is this "Kernel critical error" marked in the time as when shutdown happened. Here are screenshots, if you need a translation let me know:



















Sorry if Im beeing a bit "annoying", this is starting to frustrate me, hehe xD.


----------



## Wrench97 (May 10, 2008)

You need to use a volt meter to see if the PC is signaling the PSU to start and to see if the Pwr_Ok signal is good. I do not know of any other way to do it.




Wrench97 said:


> That does not eliminate the PSU, you have check the PWR_OK signal with a voltmeter as well as the PWR_On lead> http://www.techsupportforum.com/forums/f210/test-your-power-supply-with-a-multi-meter-151526.html


----------



## siiimmm (Apr 30, 2012)

Okay, but something I didnt get, I need to test it out with the PSU connected to the MOBO?, if so, the probe tip need to be "forced" to the back (in each pin) of the 24 pin connector?.

Stupid question, do I need to have only the 24 pin connector pluged to the mobo and then turn the PC on AND THEN test the voltages?


----------



## Wrench97 (May 10, 2008)

Leave all the wires connected, forced no if you look at the back of the connector you can see the metal pins just have to connect the - voltmeter lead to any black wire, I use one is a extra 4 pin molex hard drive plug, and probe the 24 pin connector with the + voltmeter lead.


----------



## siiimmm (Apr 30, 2012)

Alright, Imma to try to get a multimeter as soon as possible and do the test.

If I did understand correctly, this test will tell us if there is something wrong with the PSU, but most importantly, it will test us why the PC is not turning on after a shutdown (PWR_OK). Correct me if Im wrong please. Also, will this test tell us also why the PC is shutting down under load?

And again, thanks for taking the time to asnwer my silly questions. Thanks for the help.


----------



## Wrench97 (May 10, 2008)

It'll tell us why it's not turning back on, by testing the PS_On and PWR_Ok,
It may tell us why it shutting off by monitoring the 12v reading while it's running. 

Multimeter, Digital, with 8 Functions and 20 Ranges- Craftsman-Tools-Electricians Tools & Lighting-Multi-Meters & Meters


----------



## siiimmm (Apr 30, 2012)

Uhmm, whats the PSU AC ground unit?


----------



## siiimmm (Apr 30, 2012)

Okay. test "done", results:

All this test was done with the PC on and putting probe tips on the back of the 24pin connector.

1. Check Pin 9 (Purple, VSB) is about 5V. This is the standby voltage and is always on when the power supply is live to an AC source. If not 5V then problem with PSU, or a possible short circuit in motherboard or a peripheral device has caused the PSU to auto-shutdown. 

*RESULT:* 5.07v.

2. Check Pin 14 (Green, PS_On) should be about 3~5V. 

*RESULT*: 0.08v :C

If PS_On is zero Volts and VSB okay then disconnect the pc case Power On switch to see if voltage comes up, if so then bad switch. 

*RESULT:* same, 0.08v.

3. Press the pc case Power On switch and PS_On should drop to ~0V.

*RESULT:* couldnt, since the PS_On (green pin) voltage was 0.08. Still, it didnt happen nothing, it stayed at 0.08v.

_With PS_On at ~0V (0.08v)_

4. Check Pin 8 (Gray, Power_OK) should be 3~5V to signal the CPU that power is okay to start. If not above 2.5V then signal not high enough to trigger CPU for start.

*RESULTS: *looped between 4.97v and 5.01v.

5. Pressing the Reset button (or shorting the reset pins) will make Power_OK go low (0V), and when released should go back up to 3~5V.

*RESULT: *it driped to 4.95-4.96v.

_(Note, this may not happen if the manufacturer has used a 'soft' method to trigger the Reset.)_

_With Power_OK at ~5V (gray pin, 4.97v-5.01v)_

6. Refer to chart and check voltages are at proper levels on the 20-pin connector and all the peripheral power connectors inside the case.
+3.3v pins 1, 2, 11 (Orange wires) *RESULT:* 3.36V
+5V pins 4, 6, 19, 20, (Red wires) *RESULT:* 5.0V
+12V pin 10 (Yellow wires) *RESULT:* looped between 12.37v and 12.38v.
-5V pin 18 *RESULT: *white pin, PSU does not have one.
-12V pin 12 *RESULT:* -12.51v.


----------



## Wrench97 (May 10, 2008)

Monitor the 12v until the PC shuts down, when the PC shuts down and will not turn on is when you check the green wire on pin 14 to see if the Switch is signaling the PSU to turn on, if the voltage is low check the purple wire is at 5v. If the Green wire is reacting to the power switch correctly then move on to the gray wire on pin 8 Power_OK is signaling the CPU to start.


----------



## siiimmm (Apr 30, 2012)

Okay, so, when the PC shut downs I do the test again, but with the PC off?, or do I wait until it turns on again?.


----------



## Wrench97 (May 10, 2008)

When the PC shuts off and will not turn on is when you want to test the to see why it will not turn on, the PS_On and power switch tests tell you nothing if the PC is running at the time. The Green wire is a signal wire, grounding it signals the PSU to turn on. The switch on the front is a momentary switch like a door bell button, it only makes contact when pressed. With the PC off the Green wire has 3-5v pressing the power button momentarily connects it to ground the voltage drops to 0v and the psu turns on, the gray wire should then go above 3v to signal the CPU to start, if the power supply does not give the pwr_ok signal then the cpu will not start.


----------



## siiimmm (Apr 30, 2012)

Thanks for the explanation, so, while the PC is off, the green pin have to be between 3-5v so it can receive the signal from the switch to turn the PSU on, and the gray one needs to be also in the same ranges so it can gives the signal to the CPU. Correct me if Im wrong please.

Anyways, I will try to do the test again as soon as possible after a shutdown, since I will need to borrow the multimeter again, hehe.

Thanks for all the help so far.


----------



## Wrench97 (May 10, 2008)

Yes the gray wire is the Power OK signal, after the PSU starts it signals the CPU that the power is OK to start, if the Power Supply recognizes the power is not correct it will not signal the cpu to start.


----------



## siiimmm (Apr 30, 2012)

Okay, so, to get it clear, I will do these steps:

1. Check Pin 9 (Purple, VSB) is about 5V. This is the standby voltage and is always on when the power supply is live to an AC source. If not 5V then problem with PSU, or a possible short circuit in motherboard or a peripheral device has caused the PSU to auto-shutdown.
2. Check Pin 14 (Green, PS_On) should be about 3~5V. If PS_On is zero Volts and VSB okay then disconnect the pc case Power On switch to see if voltage comes up, if so then bad switch.
3. Press the pc case Power On switch and PS_On should drop to ~0V.
If no change, the suspects are faulty switch or CPU. If the motherboards PS_On pins are accessible by removing the pc case's power on leads then short the 2 pins with a light tap from a screwdriver tip to trigger the power on. Another way is to use a jumper wire to short PS_On to GND. If no change in PS_On then probable fault is CPU. 

With PS_On at ~0V...
4. Check Pin 8 (Gray, Power_OK) should be 3~5V to signal the CPU that power is okay to start. If not above 2.5V then signal not high enough to trigger CPU for start.
5. Pressing the Reset button (or shorting the reset pins) will make Power_OK go low (0V), and when released should go back up to 3~5V.
(Note, this may not happen if the manufacturer has used a 'soft' method to trigger the Reset.)
*NOTE:* If CPU doesn't POST when Power is first turned on but does POST when Reset triggered, then the initial power demand (by all devices) is to high for the PSU to handle, need to replace PSU with a better one.

After a shutdown occurs, BUT with the PC beeing off and the PSU connected to the wall and the PSU back switch on, for obvious reasons, right?

I will hopefully do the test again tomorrow.

Thanks in advance!


----------



## Wrench97 (May 10, 2008)

Yes that's how you test it.


----------



## siiimmm (Apr 30, 2012)

Well, test done.

Purple wire: 5.07v
Green wire: 3.77v.
Gray wire: 0.00v.

It seems it does not have the neccesary power to signal the CPU?.

During the test, the PC wasnt turning on by pressing power button. However, after the test, I turned the PSUs back switch off and then on, and then I was able able to turn on the PC. However, the gray wire still was 0.00v (while PC off), even though the PC was turning on already.

It seems some protecion on the PSU or something reseted when I reseted the PSU back switch.


----------



## Wrench97 (May 10, 2008)

That's is correct, when you pushed the button on the front to turn the PC on did the green wire drop to 0v, if it did and the gray never came up then it's the PSU that's shutting down. Of course turning the Switch on the psu off and back on to reset also would indicate it's the psu at fault.


----------



## siiimmm (Apr 30, 2012)

Yes, green wire went to 0.00v when the PC was finally turning on, but the gray one was only 0.00v the PC was off, and it was fine when PC was on.

Also, I noticed something "weird" when I reproduced the shutdown.

When I reproduced the issue, I had a software taking screenshot every minute to monitor temps.

See this album and see the progession of the screenshots. There are 20 screenshots, which means I was able to play 20 minutes before the shutdown. 

Photo Album - Imgur

Now, look at the PCH temperature, you can see that is getting hotter and hotter, and eventually it reach 50°C, which is when the PC shutdowns. Can it be this related to the issue?, maybe the MOBO is sending a signal to shutdown, so it can avoid damage to the MOBO itself from overheating, and then not letting the PC turning on until it cools up itself?

Thats all for now, Imma go sleep and will come back tomorrow, got test in the morning <,<.

Thanks again for all the help so far.


----------



## Wrench97 (May 10, 2008)

No the PCH will run stable into the high 70's.

When the PC shut down and would not turn on, did the green wire have have voltage and drop to 0 when the button was pushed?


----------



## siiimmm (Apr 30, 2012)

Ahhh, alright.

Yes, when PC wasnt turning ON the green wire had 3.77v, but it wasnt dropiing to 0v when pushing power button. However, gray wire was 0.00v all the time until turning PC on, which was 4.97v.


----------



## siiimmm (Apr 30, 2012)

Also, what I dont understand, if the issue is the PSU that is shutting down, why it is then ONLY hapening when the AC unit is off?, that is "suggesting" an overheating issue as I mentioned before, but looking at the temps it is not. Weird issue tho :/.


----------



## Wrench97 (May 10, 2008)

The gray wire is suppose to be at 0v until the PSU starts and senses the power is good, the PSU then signals the CPU to start by applying voltage to the gray wire.

If the green was not dropping to 0 when pressing the power button the next step is to unplug the 2 wires from the motherboard that go to the power switch and connect or _short_ the pins on the motherboard with a small screwdriver to eliminate the power switch and wiring as the source of the problem. If you also have a reset switch(not all cases do) I would also disconnect those wires from the board while testing.


----------



## Wrench97 (May 10, 2008)

siiimmm said:


> Also, what I dont understand, if the issue is the PSU that is shutting down, why it is then ONLY hapening when the AC unit is off?, that is "suggesting" an overheating issue as I mentioned before, but looking at the temps it is not. Weird issue tho :/.



There are not any temp readings for the psu(no sensors, no connection to the motherboard other then power), that's what makes the PSU the prime suspect the other temp readings are decent. It could also be something obscure like a CPU heat sink back plate shorting on the back of the board or a motherboard shorting to the case at higher temps.


----------



## siiimmm (Apr 30, 2012)

Wrench97 said:


> The gray wire is suppose to be at 0v until the PSU starts and senses the power is good, the PSU then signals the CPU to start by applying voltage to the gray wire.
> 
> If the green was not dropping to 0 when pressing the power button the next step is to unplug the 2 wires from the motherboard that go to the power switch and connect or _short_ the pins on the motherboard with a small screwdriver to eliminate the power switch and wiring as the source of the problem. If you also have a reset switch(not all cases do) I would also disconnect those wires from the board while testing.


I actually did that, but nothing happened. This can be done with ANY screwdriver?


----------



## Wrench97 (May 10, 2008)

Anything metal that makes a connection.


----------



## siiimmm (Apr 30, 2012)

Well, yeah, I did that but nothing happened.


----------



## Wrench97 (May 10, 2008)

If the green did not drop while shorting the pins, it probably is in the board.

What cooler are you using the stock Intel unit or a aftermarket(which one) unit?

It may be worthwhile to pull the board out and set it up on the bench to eliminate contact with the case as a source of the problem.> http://www.techsupportforum.com/forums/f15/how-to-bench-test-troubleshoot-your-system-262998.html


----------



## siiimmm (Apr 30, 2012)

Aftermarket cooler, Cooler Master Hyper 212+.


----------



## Wrench97 (May 10, 2008)

Ok so it does have a metal backplate on the backside of the board, I would pull the board, swap out the cooler with the stock one and run it on the bench to see if it shuts off, it still does RMA the board.


----------



## siiimmm (Apr 30, 2012)

Oh man I dont what to think about this issue... I just played 1 hour and half straight withuot shutdowns (still no shutdowns). Before I was able to only play about 10-20 minutes before shutdown.

Im starting to think it can be an issue with the graphics cards overheating, all the times shutdowns occured GPUs temps was about 70-75°C, now I did some tweaks to the AVG Pressicion software to automatically increase fan speed while temps increase. The card itself is a EVGA GTX 550 Ti in its 1GB version.

The GPUs temps was all the time about 55-65°C in this last "gaming session". 

Also, I dont if this could matters, but I remove the back side of the case, the one that is in the MOBOs side. Maybe that means better air flow, I dont know.


----------



## Wrench97 (May 10, 2008)

Those cards normally run that warm without issue. 
Plus a video card can't signal for a shut down only a CPU can.


----------



## siiimmm (Apr 30, 2012)

In the last days shutdowns have not occured, which is weird.

If it happens again I'll let you know.

I have been thiking on getting a new mobo anyways, is this a good option?

https://www.digitalife.com.mx/producto/10049/ASUS/MOTHERBOARD-P7P55D_:_E-LX-SK1156

Also, if you could explain, why does it only have 4 pins CPU connector for the mobo instead of 8?


----------



## Wrench97 (May 10, 2008)

It's a decent board, It does have a 8 pin CPU connector, the back 4 are covered with a cap that pops off because they are optional with lower wattage CPU's.

ASUS - Motherboards- ASUS P7P55D-E LX


----------



## siiimmm (Apr 30, 2012)

Hey, me again. I know it has been a long time since I posted on here, but a shutdown just happened again while gaming.

Couldnt turn the PC on for like 15 minutes, then put the PSU back switch off for 5-10 seconds, then turned it on again and was able to turn the PC on.

So, could it be definitely the PSU?, it is worth mentioning the I didnt have the AC unit on, so, why is it a PSU issue if shutdown occurs only when AC unit is off, suggesting an overheat issue?, I know we have talked about this too many times, but is something I cant still understand.

Thanks in advance again!


----------



## Wrench97 (May 10, 2008)

Having to reset via the power switch could mean the psu.


----------



## siiimmm (Apr 30, 2012)

Hey, its me again with bad news...

I finally was able to buy a PSU, I got a Corsair TX550M, but guess what?, it still shutwodns, just happened the first shutdown after I changed the PSU. I also changed the case to a Cooler Master HAF 912, if that helps.

So, the PSU wasnt the problem, Im started to think it could be faulty temp sensors with the motherboard or the motherboard itself. When a shutdown occurs, and after Im able to turn it on again, there appears in the screen a CMOS checksum error or something like that, could be that an indicator to a faulty MOBO?.

Also, it is so weird, sometimes I have to reset the back switch on the PSU so the PC can turn on again, but if it is NOT the PSU, what could it be then?. Im going to lend a GPU to test, so I can discard mine or see if the GPU is the issue, but I doubt it, because one time a shutdown occured while the PC was idle, just in the desktop, not playing games.

This issue is really pissing me off, even more now because I spent $125~ USD to get the new PSU.

Any idea on what could it be now, or how can I troubleshoot it?

Thanks in advance again!


----------



## siiimmm (Apr 30, 2012)

Hmmm, cant edit previous post. With the CMOS issue I meant this:

http://i.imgur.com/zdSvm.jpg


----------



## Wrench97 (May 10, 2008)

Looks like the board is what I thought it was, did you ever do the bench test from post #71?


----------



## siiimmm (Apr 30, 2012)

Hmm nope, I completely missed that :/.


----------



## siiimmm (Apr 30, 2012)

Besides the bench test, is there any other way to troubleshoot the mobo?


----------



## Wrench97 (May 10, 2008)

Not for shorts to the case.


----------



## siiimmm (Apr 30, 2012)

I understand, however I dont have a good place to put up all the hardware while testing. Is there another way to detect if the issue is the MOBO, besides the bench test / shorts to the case?

Thanks in advance.


----------



## Wrench97 (May 10, 2008)

Not that I've ever seen.


----------



## CactuSSPP (Jan 28, 2013)

Hello,

I have exactly the same issue with the same Motherboard, last weekend i have made the bench test, and the result was the same, when temperature was over aprox (22-23 C in the room, the PC shutdown) Configuration was: Gigabyte H55M-USB3 (Rev 2.0) latest BIOS, 2*4 Gbyte DDR3 low voltage ram, i5-650 cpu, Corsair 650W PSU, and a hitachi 250Gbyte HDD (on my desk  ) 

I have tested the CPU with Prime 95, was over 90C (room was only 19C at that time), and everything works fine. I guess the Ram should be ok, since the ram shouldn't do issue like this.

Since you have changed your PSU, i guess it's also ok, or i can test it with another PC, to be 100% sure. 

So only the Mobo can cause the issue i guess. Let me know if i am wrong. 
(I have reported the problem to Gigabyte GTS, i hope they will answer soon.)


----------

