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Question

PC Shutdown at random; Reboots without video

Apr 3, 2017 12:24PM PDT

Within the last few weeks my PC has begun shutting down seemingly at random. The system looses power, then it seems like it attempts to boot right back up except for video never comes back and also the backlighting on my keyboard does not illuminate.

I have discovered one clip going from the power supply to the motherboard that I can sometimes fiddle with the wires leading into the clip that will allow the system to reboot normally but the problem persists.

I was thinking that perhaps the system is not longer getting enough juice from the power supply for some reason but wanted to run this by bigger brains than my own in the event there may be something that I am overlooking.

Thanks in advance!

Discussion is locked

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Answer
This is roughly my system build....
Apr 3, 2017 12:44PM PDT
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Answer
That's a bad PSU.
Apr 3, 2017 12:49PM PDT

"Output
+3.3V@25A, +5V@25A, +12V1@20A, +12V2@20A, +12V3@20A, +12V4@20A, +5Vsb@3A, -12V@0.8A "

With only 20A on any +12V rail, it's far too easy for the PSU to be overtaxed. Good number of Watts but too many rails. Swap this for a single rail of same Watts then re-test.

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Thanks for the tip.
Apr 3, 2017 12:52PM PDT

Thanks for the info. I was thinking I was clear on wattage but I'm a bit clueless on anything beyond that power wise. Just assuming that perhaps use over the past year had degraded the output enough to start the problem.

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Free temporary workaround.
Apr 3, 2017 12:58PM PDT

Unplug the optical drive and what else?
Try another connection to the GPU.

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No dice :(
Apr 4, 2017 5:31PM PDT

Gave this a go with no results however I do believe I've isolated the issue more specifically. There is a connector running from the PSU to a clip on the motherboard that when fiddled with (slight bending of the wires in one direction left or right on the back side of the clip) will either allow the pc to get power or not. I am hopeful that the problem is still on the PSU side and not an issue with the connector on the motherboard.

Suppose at this point its just replace the PSU and if that doesnt resolve the issue look at possible motherboard replacement is what I'm thinking.

Thanks again for the feedback and feel free to keep it coming if you think I may be on the wrong path. Happy

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Fiddling? Next idea.
Apr 4, 2017 6:13PM PDT

Those are MOLEX connections and the female ends can spread and this happens. You sort of have to know how these are made to know you can jam in a small flat head and tighten up the fit.

But the PSU isn't that great to bad (too many rails). It's got plenty of Watts but too many rails. The RM60 noted below is a good choice as well as most in the top 10 at the Best Sellers.
https://www.amazon.com/gp/bestsellers/pc/1161760/ref=pd_zg_hrsr_pc_1_3_last

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MOLEX
Apr 4, 2017 6:43PM PDT

Are these MOLEX connections on both ends of that clip or just the mobo/psu end?

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Clarification...
Apr 4, 2017 6:44PM PDT

Sorry what I meant was is that just on the mobo side of the connector or the cable leading off the psu that can be tightened.

Thanks again for the advice!

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Remember it is fiddling.
Apr 5, 2017 9:35AM PDT

If you were here I could show this in about 15 seconds. So I write it and hope you can see how the common Molex can spread and lose contact.

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If the OP prefers
Apr 4, 2017 5:44PM PDT
EVGA < this one would be an example
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Thanks for the recommendation.
Apr 4, 2017 5:51PM PDT

I don't really have a brand preference just more of a bang for buck type of consumer. Silly I'm figuring at least a 750w or better as a replacement so I appreciate the suggestion.

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Not a recommendation
Apr 4, 2017 6:03PM PDT

that's just a for instance.
Personally I wouldn't buy that PSU.
No Off Button.

The one I Own .....

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Answer
Clip
Apr 3, 2017 5:43PM PDT

Take that plug off/on 5 or 6 times.....test

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Alas...
Apr 4, 2017 5:32PM PDT

Tried that to no avail. The tinkering continues!