Question My desktop PC won't easily power on after it's been unplugged or after a power outage ?

[Badbreath]

Hello to everyone,

Forgive me for any mistakes, as this is my first post here.

I have a strange issue with my desktop PC and I wonder if anyone can help a bit.

Every time I unplug it or when power gets cut off, I struggle to power it back on.
Power button doesn't work and then also the buttons on the motherboard don't work (power button, reset button, and jumper button).
At the same time, all peripherals connected to the pc, USB devices are getting power and the motherboard gets warmed up in a few spots near the buttons.

While pressing the buttons at random, at some point the PC fires up and starts working properly.

Anyone has the slightest idea about this issue?
What information could I provide in detail to help you help me?

Thanks a lot for your time.

 

[rgd1101]

full system spec? include brand and model of the psu

 

[Misgar]

How old is the PSU? If it's getting old, it may be on its way out and in need of replacement. If you have another suitable PSU, try it in the PC.

 

[Badbreath]

CPU: Intel(R) Core(TM) i5-4690K CPU @ 3.50GHz 3.50 GHz
with
Cooling: Corsair hydro H100
GPU: Gigabyte Windforce GV-N760OC-4GD
MB: Asrock Z97 Extreme
PSU: Corsair RM750 80+ Gold cert
RAM: 2* Corsair Dominator Platinum 16 Dual (2x8 sticks) sets (PC only recognizes 16GB ram tho after upgrading to:
System: Win10Pro version. 22H2 (64bit)
1 mechanical Drive and one SSD

The system suddenly, as expected booted again...
I have tried booting it:
1 - without GPU, RAM, Hard drives,
2 - just the GPU
3 - just the RAM
4 - just the the drives
5 - GPU, RAM

didn't boot at any of these circumstances and occasions.

It suddenly booted, while I was attempting to reconnect the hard drives, driving me crazy...
System was build around 2012-14 as far as I am aware.

Questions:
1 - how can I test what is the issue with booting once the power is completely cut off? (power outage or just unplugging the cord)
2 - what is the deal with the RAM stick? I should have 32MB, not just 16MB,,,

Thanks for your time and tips

 

[Misgar]

I'm just about to go round to a friend's house to sort out his ancient AMD Phenom II X4 965 with a similar problem. I'll report back after I've swapped out every single component, if I find anything useful.

If you fit 4 x 8GB DIMMs and Windows only sees 16GB, one of your CPUs memory channels might be dead. Try fitting one pair of DIMMs, see if you get 16GB, then fit the other pair in their place and see if you get 16GB. That way you'll know that both pairs are recognised. Repeat the above using the other two RAM sockets on your mobo.