New psu not powering pc

idkfa · 11 Oct 2020 at 15:38

Hi all,

I just swapped out an aging psu for a Corsair HX1200i. The problem is when powering on all the fans come on and the light on the cpu cooler flashes but there is no boot or post. System worked fine before the swap. There does not appear to be a short, have I got a bad psu? Any suggestions for what to try? Many thanks in advance.

OvEr_KiLL · 11 Oct 2020 at 16:22

unplug the wall plug from it, and re check all the cables and make sure you use 1 cable per power slot on graphic cards, ie. 2x8pin slots you want 2 cables no daisy chain(splitters)
edit. try it without the usb link thing, read someone else had problems with it and he changed this in the bios
It is as simple as entering bios and put "power on" in option "restore on ac/power loss".

idkfa · 11 Oct 2020 at 17:19

Thanks for the reply. I have checked the cables and all looks good and gfx has 1 cable per power pin. I have just put the old PSU back in and everything is working. I read online that the CPU power can be in any of the ports labelled 6+2 PCIe and 4+4 CPU, is this true?

DoneADougalOnSofa · 11 Oct 2020 at 17:43

Assuming your old PSU was modular, you aren't using (accidentally or otherwise) any of the old PSU's cables, are you?
The pinouts can be different between brands, and I have had it happen with EVGA PCIe cables when I switched to an XFX unit- no booty.

idkfa · 11 Oct 2020 at 17:47

That could be it. The old one is an Enermax and I left one of the sata power chains connected. It only had a HDD and DVD drive attached do you think that's it?

EsaT · 11 Oct 2020 at 18:05

You better hope those drives aren't toast.
PC parts don't take lightly possibly inverted polarity or even higher up voltage.

Btw, have to wonder how many understands your forum user name...

Grimley · 11 Oct 2020 at 18:10

EsaT said:
Btw, have to wonder how many understands your forum user name...

I do - its a cheat code for the original DOOM!

DoneADougalOnSofa · 11 Oct 2020 at 18:10

idkfa said:
That could be it. The old one is an Enermax and I left one of the sata power chains connected. It only had a HDD and DVD drive attached do you think that's it?

I'd say it's a fair chance.

Totally unplug the SATA cables at the PSU end to test. It should hopefully post and show a no boot-drive error.

idkfa · 11 Oct 2020 at 18:19

DoneADougalOnSofa said:
I'd say it's a fair chance.

Totally unplug the SATA cables at the PSU end to test. It should hopefully post and show a no boot-drive error.

The connected drive was just a data drive not my OS, it seems fine as is the DVD drive which is good. Will swap out the PSU again and try without using any of the old PSU cables, thanks all and yes I am a huge Doom Fan

idkfa · 12 Oct 2020 at 11:03

Hmm swapped out the old cable and the cpu cooler and all case fans and lights come on now but its restarting every 5 seconds without even posting. I have removed all braided cables and only used the corsair provided cables. Bios reset but it's doing the same thing. Any ideas?

mickyflinn · 12 Oct 2020 at 12:21

idkfa said:
Hmm swapped out the old cable and the cpu cooler and all case fans and lights come on now but its restarting every 5 seconds without even posting. I have removed all braided cables and only used the corsair provided cables. Bios reset but it's doing the same thing. Any ideas?

IS the cpu cooler to tight ? Any diag lights

idkfa · 12 Oct 2020 at 12:24

It's working fine with the old psu. I tried removing the GPU to rule out power to that but it's still on the 5 second cycle. It really seems like it's the 24 pin atx or the cpu power but I don't know what's wrong.

The motherboard is not powering on so no diag lights on it.

phil-k · 12 Oct 2020 at 13:04

even if you use the new cables , one could be faulty, I have had this in the past

mickyflinn · 12 Oct 2020 at 13:07

So the system is working fine with the old psu and boot cycles with the new.

Could be a faulty psu

Any damage to any of the new cables ?

The new ps

idkfa · 12 Oct 2020 at 17:28

I think you are right its either a cable or the PSU. It comes with 2 CPU cables and I tried both. Swapped back to the old PSU again and all is okay. Is it worth raising with Corsair or just RMA?

chrcoluk · 12 Oct 2020 at 17:31

if its new from retailer, send back to retailer, far quicker than manufacturer.

Dont tell them, you used wrong cable though.

mickyflinn · 12 Oct 2020 at 17:44

idkfa said:
I think you are right its either a cable or the PSU. It comes with 2 CPU cables and I tried both. Swapped back to the old PSU again and all is okay. Is it worth raising with Corsair or just RMA?

Send it back to the retailer of under 12 months old.

Amidar · 13 Oct 2020 at 10:28

Bought a Corsair HX1200i 2 weeks ago and fitted it 2 days ago ended up doing the never ending boot cycle. Refitted the original 7 year old power supply and the computer boots fine.