Question PC Suddenly Shut Off— Wont

dekal35

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Hello,

I was using my computer earlier today when suddenly it powered off. No smoke, nothing appeared amiss.

After attempting to reboot twice, once immediately and once after unplugging everything and waiting an hour, I’m not sure what to do.

I am running a SuperNova 850P2 PS and a Gigabyte Z170X Gaming 7 MB. When the power cable is connected, there is a button that is illuminated on the MB. Red/Pink in color and appears to be another Power Button given the logo. Nothing happens when I press this directly on the MB. The only other thing I’ve noticed is if I hold the power button on the case, after about 5 second, I hear a click coming from the power supply.

Does this sound like a blown PS? I don’t have other PCs to swap it into to check.
Any suggestions greatly appreciated and welcome...

thank you for the time.
 
How old is your EVGA P2 power supply? How long has it been in service?

Try flipping the switch on the back of the power supply to the off position "0", and then unplugging the cord from the wall or the PSU for about five minutes to allow the power supply to reset itself. Then plug the unit back in and flip the unit back to the on "I" position and try to start the system. Try to note whether or not the fan comes on the PSU, even momentarily, and whether there are full, normal lights, even if it shuts down again.

It might also be a good idea to do both of the following, conditional upon what you are able to do based on what you have access to. If you have access to a volt meter doing the full basic tests is a good idea but lets at least get an idea of whether the unit even comes on when it is not connected to the motherboard.




View: https://www.youtube.com/watch?v=ac7YMUcMjbw
 

dekal35

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Thank you very much for the prompt response.
The entire rig was built with new parts 3 years ago. I’ve tried to do the I/O flip, powering off, etc. Nothing comes on fan wise, not even briefly. Only change is the power button on the MB illuminates.

no volt meter but will buy tomorrow for future use.
Only other measurable activity I notice is the clicking sound when power button on the case is held down for 5-10 seconds...
 

dekal35

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Thank you DSzymborski. I bought the PS off Amazon. Any experience knowing if EVGA will honor it? I will call tomorrow to inquire.

would you recommend still doing the volt measure test tomorrow along with the paper clip shorting trick? If it powers up, aren’t I up <Mod Edit> creek as they say? Would then be a wiring issue or mobo?
 
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Have you FULLY disconnected ALL of the leads to the motherboard and other devices, from the PSU, AND unplugged the unit from the wall, AND flipped the power switch off and then back on after five minutes, before testing with the paper clip to see if the PSU fan comes on? If there is a problem with a device OTHER than the PSU, and it is still connected, then the protections inside the PSU are likely to simply not allow it to kick on. If you have not done that, exactly as outlined, then you need to do so. There is no other way to determine if there is a PSU ONLY issue or if something else is involved, in quick and basic manner other than getting a PSU tester and you will STILL need to disconnect the PSU from the rest of the hardware to do so accurately.

If the fan does not come on on the PSU after disconnecting it from the rest of the hardware, and power cycling it to reset any protections, then the PSU is dead. If it DOES come on, then it still MIGHT be bad, but at least it isn't fully dead and you can move on reconnecting things one at a time until it doesn't come on anymore, to determine if it's motherboard, storage device, etc., causing the problem, or something else.

Probably also a good idea while it's all disconnected to make sure the graphics card and memory are fully and properly seated, especially if you've recently done anything at all inside the case prior to this problem occuring because you might have inadvertently knocked something loose just a little bit.

Probably it's the PSU, but I'd want to eliminate as many possibilities as you can before simply condemning it.

It could just as well be the motherboard as the PSU. Those lights, mean nothing really.
 

dekal35

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Have you FULLY disconnected ALL of the leads to the motherboard and other devices, from the PSU, AND unplugged the unit from the wall, AND flipped the power switch off and then back on after five minutes, before testing with the paper clip to see if the PSU fan comes on? If there is a problem with a device OTHER than the PSU, and it is still connected, then the protections inside the PSU are likely to simply not allow it to kick on. If you have not done that, exactly as outlined, then you need to do so. There is no other way to determine if there is a PSU ONLY issue or if something else is involved, in quick and basic manner other than getting a PSU tester and you will STILL need to disconnect the PSU from the rest of the hardware to do so accurately.

If the fan does not come on on the PSU after disconnecting it from the rest of the hardware, and power cycling it to reset any protections, then the PSU is dead. If it DOES come on, then it still MIGHT be bad, but at least it isn't fully dead and you can move on reconnecting things one at a time until it doesn't come on anymore, to determine if it's motherboard, storage device, etc., causing the problem, or something else.

Probably also a good idea while it's all disconnected to make sure the graphics card and memory are fully and properly seated, especially if you've recently done anything at all inside the case prior to this problem occuring because you might have inadvertently knocked something loose just a little bit.

Probably it's the PSU, but I'd want to eliminate as many possibilities as you can before simply condemning it.

It could just as well be the motherboard as the PSU. Those lights, mean nothing really.


No. I have not and will do this in the AM to be sure. Thank you for the suggestion. I wasn’t aware of these safety provisions that could cause another piece of hardware from preventing a boot from the prior “on” period. Sorry if the phrasing isn’t exactly accurate but I think I understand your point.
I’ll unplug everything from the PS tomorrow before trying anything else as I’ve only unplugged the Ps from the outlet tonight along with the I/O switch.
 

dekal35

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Have you FULLY disconnected ALL of the leads to the motherboard and other devices, from the PSU, AND unplugged the unit from the wall, AND flipped the power switch off and then back on after five minutes, before testing with the paper clip to see if the PSU fan comes on? If there is a problem with a device OTHER than the PSU, and it is still connected, then the protections inside the PSU are likely to simply not allow it to kick on. If you have not done that, exactly as outlined, then you need to do so. There is no other way to determine if there is a PSU ONLY issue or if something else is involved, in quick and basic manner other than getting a PSU tester and you will STILL need to disconnect the PSU from the rest of the hardware to do so accurately.

If the fan does not come on on the PSU after disconnecting it from the rest of the hardware, and power cycling it to reset any protections, then the PSU is dead. If it DOES come on, then it still MIGHT be bad, but at least it isn't fully dead and you can move on reconnecting things one at a time until it doesn't come on anymore, to determine if it's motherboard, storage device, etc., causing the problem, or something else.

Probably also a good idea while it's all disconnected to make sure the graphics card and memory are fully and properly seated, especially if you've recently done anything at all inside the case prior to this problem occuring because you might have inadvertently knocked something loose just a little bit.

Probably it's the PSU, but I'd want to eliminate as many possibilities as you can before simply condemning it.

It could just as well be the motherboard as the PSU. Those lights, mean nothing really.

Quick follow up, when you say power cycling, that is the process of unplugging all leads from hardware units to PSU, correct?
 
Actually, it's the process of turning the switch on the back of the PSU to the off or 0 position, then unplugging it from the wall, BUT you need to have all the hardware disconnected before you turn the PSU back on otherwise it's just going to trip the protections again instantly if there is a short or other current/voltage problem somewhere.

AND, when I say "before you turn it back on", I mean before you plug the unit back into the wall socket and flip the switch on the back of the PSU back to the "I" position.
 

dekal35

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Hello. So, here’s what I’ve found. Breeze, I started with your advice and as opposed to unplugging everything, went piece by piece to see if I can isolate the issue.

The PC boots when the video card is unplugged and removed.
When I plug it back in, power button does nothing and nothing posts. I’ve tried plugging it into another free slot, same thing.

it’s clear that it’s not a power supply issue but it appears to be a GPU issue? I am currently running a EVGA GeForce GTX 980ti. Is it safe to assume that I’ve correctly identified the problem?

anything that I can do to confirm that it is fried or is there a way to bring it back?
 
Not necessarily. It could be a problem with the PCI power circuit on the PSU that supplies power to the 6 or 8 pin connectors.

I would agree that it is MORE likely that it is the graphics card, but I'd probably want to at least TRY using that card in another system or try using a different power supply in this one, to see if there is any difference with a different power supply. Obviously the graphics card is likely the older component here, so it's more likely to be at fault, but it is possible still that it is a PSU issue if the problem is only on the circuit that powers the graphics card through it's PCI connectors.

I'd say it's likely that you've ruled out everything else though.
 

dstln

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Looks like the PSU has a 10-year warranty. EVGA has had decent warranty support with their GPUs, I wouldn't worry about warranty issues here either if the power supply is indeed dead.
 

InvalidError

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If you have a multi-meter, you could try measuring resistance from 12V input on the GPU to ground. On most VRMs, you will see 100+ ohms of resistance when the VRM has insufficient voltage to start, though you may need to wait a few seconds for input caps to charge before readings stabilize. If a shorted GPU is tripping over-current protections on the PSU, that measurement should be well below 1 ohm, too low to measure with any sort of accuracy using a cheap meter so we'll just call that a dead short. If you read a short on the GPU's 12V input, then something is definitely wrong with it, such as a busted high-side FET sending 12V to Vcore or Vgddr.