[SOLVED] Installed New PSU, Computer Won't Boot. Old PSU Won't Work Now Either

[ZorakXT]

Specs:
Case - Silverstone RVZ03-ARGB
MB - Asus Rog Strix B460-I Gaming
PSU - (New) Corsair CX 450M
(Old) Corsair CV 55
CPU - Intel Core i3-10100
Graphics Card - MSI Geforce GTX 980
RAM - Corsair CMK8GX4M2A2666C16R LPX 8GB (2 x 4GB)
Hard Drive - Samsung 860 Evo 1 TB
OS - Windows 10 Pro

Hello, I just installed a new PSU (CX 450M) in my setup and now my computer won't boot. No lights come on and the fan doesn't even start at all. Hoping someone can help.

There was nothing wrong with the old PSU, I just wanted to get the new one for cable management reasons as the old one was not modular at all and had several cables I had no use for.

After not being able to power on the computer with the new PSU, I switched back to the old one, but the same thing happens. My computer won't boot up at all, not even for a split second.

I checked and double checked the power switches, cables, and connections. I ensured that all the cables were seated correctly, especially the power to the CPU and motherboard. Still nothing. I made sure to ground myself before working on the computer. Other things I've tried (all with the old PSU after it wasn't working either):
-Unplugging all unnecessary attachments.
-Connecting only the PSU to the motherboard with the power switches.
-Checking power and switch cables for signs of damage. None were found.

I'm at a loss as to how to proceed from here. I saw something about clearing the CMOS, which I'll try as well. Any help would?be greatly appreciated, thank you.

EDIT:
I tested the motherboard by hooking it up to my sister's case and PSU. It turned on and stayed on, so my motherboard doesn't seem to be the issue. I'm wondering if perhaps it's the case itself and somehow the power switch got damaged.

Also tested both PSUs on her computer and both seem to be working fine. It's got to be the power switch cables from the case not transmitting the signal for whatever reason.

 

[eszed556]

Hi. When I ran into a similar situation a decade ago I learned how to turn on my PC w/o a power switch on the case. I used a screw driver to connect the power pins on the motherboard.

I searched on YouTube for a short video tutorial -

View: https://www.youtube.com/watch?v=G4FOBL1c3pA

This is just to rule out other issues because it seems you've done a fair deal of troubleshooting. It may look risky so tread carefully should you need to.


If your system turns on, your components are good and perhaps you can look into replacing the power switch and/or wires for your casing.

 

[ZorakXT]

Hi. When I ran into a similar situation a decade ago I learned how to turn on my PC w/o a power switch on the case. I used a screw driver to connect the power pins on the motherboard.

I searched on YouTube for a short video tutorial -

View: https://www.youtube.com/watch?v=G4FOBL1c3pA

This is just to rule out other issues because it seems you've done a fair deal of troubleshooting. It may look risky so tread carefully should you need to.


If your system turns on, your components are good and perhaps you can look into replacing the power switch and/or wires for your casing.

Thanks for the reply. I believe for whatever reason the power switch itself got damaged somehow during installation. I tested all the other components with my sister's computer and everything worked fine. It was only when I tried plugging it back into my case that the problem occurs. I'll try the trick in the video you posted, thanks!

Tried the method in the video and motherboard booted right up. I guess it is the power switch after all.

It's definitely something going on with the power switch/cable. I switched it with the reset cable and the computer powers on just fine with the reset button.

 

[eszed556]

I'm glad to read that. You should be able to find a replacement power switch and/or cable if its a generic design - but you can deprioritize it if you can live with the reset button doing the job instead.