Please help me with my first PC build

Hello Tek syndicate, Its been a while since I was last around here and I hope you've all been doing well. Whilst I was away, I was mostly saving up for my Desktop PC parts, which me and my family had considered my 'Shangri-la'.

Anyway, Ive started the build watching over Logan's old PC build video and being very careful with the component and making sure not to handle them roughly, or add them all in at once before they could be tested.

My main issue is something between the motherboard and the PSU I believe. You see, I have the motherboard fitted, and hooked up to the PSU, built in fans and also the graphics card since the motherboard doesn't have one built in. When turning on the power and turning on the machine, it usually shuts down completely after about 30 seconds ~ 1 minute. The computer can simply be switched on again, however to on time usually decreases with subsequent restarts. This is the main problem I have so far.

Sometimes I have just been able to get the BIOS up on the screen before it shuts down, so unfortunately I cant really run tests through the BIOS to diagnose the problem. I have a suspicion that it is the 24 pin ATX connector from my PSU to the motherboard as it cannot fully clip into place. I have fully made sure that they are the right connectors to the sockets etc, checking through the manuals as well. The heads go in 90% of the way, but will not clip, no matter how much pressure i add.

I'm just trying to be very careful here as I don't want to break anything on installation.

Has anyone else experienced this problem before, any prior knowledge would be extremely helpful.

Current parts are:

  • ASRock X99X Killer S2011-3 ATX
  • Corsair HX750i PSU
  • Intel Core i7 5820K
  • Corsasir DDR4 32GB Vengeance LPX Red Memory
  • 6GB EVGA GTX 980 Ti
  • NH-U12S Noctua CPU COOLER
  • Corsair 230T Orange + Window
  • 4TB WD SATA 3 HDD

Any help or advice would be immensely appreciated.

hmm thats weird, the 24pin connector should basicly clip into place.
double check if there isnt anything weird with the wires of the powerplug.

maybe you could try to take everything out of the case, lay the mobo on its box,
then connect the psu, put in the gpu, and ram, and see if it boots normaly then.

If i remember right, Logan also had some issues with his corsair psu, with connecting powerplugs.
but that was on the modular psu side.

Thanks for your advice, I shall have to try this later this evening when I get some free time.
To be honest, I have a fear of touching my motherboard too much, knowing about how some stuff can short out, but ill have to try and workaround using the corners.

I believe that It is a fully modular PSU that I am working with, but I am curious as to how that would be greatly different to a non-modular one? I managed to find a link with the PSU if that is of greater help to everyone out there. Thanks for the help so far!

Corsair HX750i Fully Modular power supply

there isnt realy any diffrence according to modular and semi modular psuĀ“s basicly.
Your psu is fully modular yes.

It should fit in place, but somethimes, it could be a bit harder to fiddle them it.
If you realy cant get it in properly, then it would contact the seller, and send back the psu.
It should clip in place.

I tried what you said about laying the motherboard out on its box, and connecting the essentials to test them. I managed to connect the 24 pin ATX cable properly in the end, all else I had were the RAM, CPU, Graphics card and what I think was the necessary power parts.

I kept having the same problem as before however, the GPU would run and the BIOS would show on the screen for about 30 seconds and then just shut down. I also tested this on my older, working Graphics card and still had the same result. it feels strange, yet I feel like i've narrowed down the problem a bit. I am tied between the motherboard and the PSU, but even when the other components shut down the Motherboards lights stayed on.

The mystery deepens.