[SOLVED] PC won't power on after sleep mode

[YM2992]

Hi, my PC has randomly stopped powering on after sleep mode on windows 10. During the sleep mode to wake it up I tried pressing the keys on the keyboard, clicking my mouse and pressing the power button. I noticed when I clicked my mouse the LEDs lit up but nothing else. Those didn't work so I eventually tried to hold the power button to force shutdown the PC with no response. I switched it off at the PSU and unplugged/replugged the power chord yet it still won't boot. I can see on the GPU there's a white LED light that shows it getting power so I'm not sure if power is an issue. This issue has happened to me only once before a couple of days ago but it turned back on a few minutes after. Today I've had no luck.

Here are things I've tried so far:

• Switching the PSU off and pressing the power button (a couple times with the chord connect and a couple with it disconnected).
• Removing and replacing the GPU and RAM sticks.
• Removing and replacing the case power/led pin headers.
• Shorting the power pins with a piece of metal.
• Removing and replacing the ATX connectors to the power supply/motherboard.
• Removing the CMOS battery and replacing it 5 mins after.

If you've got any suggestions or have experienced this issue, please let me know.

Specs:
Motherboard: ASROCK B450 PRO4
GPU: ASUS GTX 1060-6GB
CPU: Ryzen 5 2600
PSU: RM550x
RAM: Corsair Vengeance DDR4 3200MHz 8GB (x2)

 

[Lutfij]

How old is the PSU in your build? What BIOS version are you on for your motherboard? As for your OS, if you're on Windows 10, what version(not edition) of the OS are you working with?

 

[YM2992]

How old is the PSU in your build? What BIOS version are you on for your motherboard? As for your OS, if you're on Windows 10, what version(not edition) of the OS are you working with?

I built the PC near the end of 2019 with all new parts. From this post I can see my PSU is the 2018 version. I am unsure of my BIOS version and am on the latest (I believe) windows 10 version.

 

[YM2992]

UPDATE: I continued testing and plugged in a USB LED monitor light that I recently started using. This was connected to the USB ports on the motherboard and when connected to the port that it was previously connected to, it began flickering between warm and cool light modes and was unable to change brightness. After connecting it to a different USB port on the motherboard to test, it worked fine. The PC still does not power on. Did I fry my motherboard?

 

[thororo]

Did you make it turn on? and what was the problem if you did?

 

[YM2992]

Did you make it turn on? and what was the problem if you did?

I ended up testing the power supply and it worked, I was going to test the motherboard with a motherboard speaker I had bought but once I had, everything started to work again.

This issue happened again a couple days later, and powered on again after testing, and I realised that it may have been the 24pin motherboard cable being bent that could have been the issue. Once I straightened the cable where it meets the PSU and motherboard (the bulge of what seems to be heatshrink) the PC works as expected.