PC will not power on

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with regard to the new unit then i guess its a fully modular unit, you did remember to plug in both ends of the 24 pin on the psu side, if you only plug one half in there will be no power at all, can be easily done tbh, so just double check to be sure
Yup both bits are plugged in

My old unit was also modular (Fairly new thing at the time of it's creation I think) and was working fine with this motherboard and CPU. Then I started having this power issue and swapped the PSU, leading to the same results.
 
Soldato
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????? man this is a tricky one, last thing you could try is take the cpu,ram and storage drives off, then try and power on the board if it suddenly turns on then start adding components back one at a time and repeat until you get the no power issue, at every stage power down to avoid damage, may give you some incling as to what is going wrong
 
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????? man this is a tricky one, last thing you could try is take the cpu,ram and storage drives off, then try and power on the board if it suddenly turns on then start adding components back and repeat until you get the no power issue, at every stage power down to avoid damage, may give you some incling as to what is going wrong

I think I might have to at this point - I've been building/maintaining my own PC for 10+ years and I've never had problems like with this current build!

I'll let you know how it goes...
 
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Okay, so I just unplugged all components from the motherboard. It's literally just the PSU and the motherboard. The motherboard is receiving power (can see from the power button being lit up same as before) but it's still not powering on, and the PSU makes the same noise.

As I said before, the PSU has a built in self tester and that works, so all signs point to the motherboard right?
 
Soldato
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whops yeah cpu and cooler, but be sure to not over tighten, just a heads up you have a max 15 posts a day so you have 2 left publically you can use, by all means drop me a msg and i can assist further
 
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whops yeah cpu and cooler, but be sure to not over tighten, just a heads up you have a max 15 posts a day so you have 2 left publically you can use, by all means drop me a msg and i can assist further

I just attached the CPU cooler (fresh thermal paste, not too tight) and plugged in the 2 necessary cables to the motherboard (CPU fan, and USB for the controller box). Same results.

Also noted! I might DM you on reply to your next post, thanks!
 
Soldato
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Have a spare GPU to try?

Any debug lights / post code showing on the motherboard?

Tried a different monitor / tv with a different cable / port?
 
Soldato
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As for the sound, when I breadboard test is there is a slight sound that omits from the PSU the first time I attempt to power it on. I then have to turn it off at the wall to get it to make the same sound.

Points to a short or overload somewhere stopping the PSU starting up? is there any way of testing resistance to ground? Tricky! Washer or metal flake somewhere on PCB . . .

Can you measure 12v anywhere?
 
Soldato
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been talking with the op last night about the above issue and so far has done the follwoing

removed everything from the motherbard and still no power on though mobo led was on indicating the board was getting some kind of power, next installed their 5950x and stil no power on, then installed the ram 1 stick at a time and in slots 2 and 4 but still no joy (mobo led was on throughout the above steps but again no power up), at this point we stopped and came to the conclusion that the motherboard is a dud, the op said the quality of the board isnt great as the m.2 standoff keeps falling out, but that was earlier before we tried the above steps.

note to op as above check over your board carefully for any metal flakes or washers that may be causing a short, if you find nothing then the board is at fault
 
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I was suspecting that.
Call me cynical, but I tend not to 100% trust a retailers claim to have tested it (you can't rule out deception or incompetence).
Like I wouldn't 100% trust the 'PSU self-test', but as he said he tested two.
I wish you good luck in getting the retailer to accept fault.
 
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What you really need is a similar / duplicate motherboard. Connect everything to new mb step by step and see if it all works! If only you could borrow similar mb!
 
Soldato
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Check the PSU connectors, the pins on the inside of the plastic cover to make sure nothing is burnt. It sounds like a short, if you've replaced literally everything i would still think it was the psu even if it is a new one.
 
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Hi all
As a follow up to close this post, I've finally got my PC back up and running.

I'd been supplied with the incorrect 8-pin for my PSU from an online retailer. Apparently there's a difference between brands, and I'd been sent an 8-pin CPU power cable for an EVGA power supply and not for a Corsair power supply.

Due to my RMA's any potential damage from the wrong cable has been nullified and after being powered on for a few hours now, doing high intensity work, everything seems to be behaving as expected!

Let that be a warning to anyone else who might be having power-on issues. Ensure you're working with the correct brand of power cable suitable for your PSU!
 
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