Question Computer turns off 10-15 seconds after powering on

[carrotinaparrot]

After 5 years my computer recently started turning off 10-15 seconds after powering it on and I can't seem to figure out which part of my pc is broken. When I first turned my pc on the red led lights on the mobo flashed in this order in a quick succession, cpu, ram, cpu, ram, stays on vga for a couple of seconds and then switches to the cpu light where it turns off instantly. I tried to turn it on again and this time it almost followed the same order but instead it switched from the vga led to the boot device led and turned off immediately again when it flashed the cpu light right after. I made sure to check that all the wires were tightly fitted and then took apart the cpu, ram, and gpu and arranged them in different orders. Whenever the cpu was plugged in with any combination of the other 2 or by itself, my pc would shut off as normal but when I removed it and kept a combination of the ram or gpu in place, the cpu led would light up and stay on without the pc turning off at all. I checked the cpu and none of the pins are bent and the cpu fan turns on just fine when it's powered on. I also took out the CMOS for 15 minutes and held the bios button on my motherboard but nothing seemed to work at all. I found the motherboard manual online but I couldn't find any information on what the led lights indicate when they light up or what order they should flash in. It only said that certain led lights stay on when there is an issue with that component. It would be greatly appreciated if anyone could help me, thank you! =)

Motherboard Manual: https://images10.newegg.com/UploadF...ce/ASUS/E7472_M5A99FX_PRO_R21401484751352.pdf Page 1-27 titled 1.2.8 Onboard LED or page 41 in the pdf

GPU: ASUS STRIX Radeon R9 380
MOBO: ASUS m5a99fx pro r2.0
CPU: AMD FX-Series FX-8350
RAM: Kingston Fury Hyperx Desktop Gaming RAM Memory Ddr3 16gb (2x8gb) Hx316c10fbk2/16
PSU: EVGA 600 B1, 80+ BRONZE 600W

 

[Ralston18]

Is that EVGA PSU the original PSU?

What error codes, warnings, or even informational events do you find in Reliability History and Event Viewer?

Any specific errors, etc., occurring just before or at the time that your computer turns off?

A pattern of increasing numbers of varying errors suggests a failing/faltering PSU.

 

[carrotinaparrot]

Is that EVGA PSU the original PSU?

What error codes, warnings, or even informational events do you find in Reliability History and Event Viewer?

Any specific errors, etc., occurring just before or at the time that your computer turns off?

A pattern of increasing numbers of varying errors suggests a failing/faltering PSU.

The EVGA PSU is the original PSU and it is a prebuilt computer, none of the parts have been changed since originally being built

I can't get my pc to actually finishing POST, once I power it on it turns off 10-15 seconds later so I can't view the Reliability History and Event Viewer either

The only reason I don't think it's a faltering PSU is because the pc will stay on when a cpu isn't in place but will turn off otherwise, but I'm not sure if that's any reason to not suspect the PSU as failing.

 

[Ralston18]

PSU's provide three different voltages (3, 5, and 12) to varying system components.

So if there is a problem with any given voltage then there may be indeed be some components "on" and other components "off".

A five year old PSU, especially if used for heavy gaming, is certainly a suspect. PSU may be nearing its' designed in EOL (End of Life).

Are you able to obtain another known working PSU to swap in and test?

Remember, if modular, use only the cables that come with the test PSU.