[SOLVED] PC powers on but no display + holding power button doesn't turn it off + keyboard lights off

[AbsltZero]

Recently while I was playing XCOM 2 and talking to a few friends over discord, my entire computer suddently froze. After a few seconds of not responding I had to flip the PSU switch to turn the computer off.

After that, when I tried to turn the computer back on, the fans and case lights turned on like normal but the monitor would only display "No Signal". In addition, the mouse and keyboard lights wouldn't turn on, so it also wasn't booting.

When I try to turn it off by holding the power button for a few seconds, instead of turning off, the power and Motherboard LEDs start blinking after holding the button for around 4 seconds and then stop blinking when I let go.

One thing I should mention is that when playing some more demanding games, whenever I put my hand on the computer case it would feel pretty hot.
Not hot enough to make me want to immediatlely remove my hand from the case, but it felt hotter than it should be (though I'm not too sure). Unfortunately I wasn't monitoring the temperature so I can't say any exact numbers.

A few things that I have tried:

• Removed the video card and plugged the HDMI on the motherboard.
• Removed the CMOS battery and waited a minute before putting it back in.
• Tried swapping RAM slots or only using one memory stick.
• Swapped the PSU with my brother's PSU by connecting it only to the motherboard, the CPU power connector and one SSD. Only one RAM stick connected and no GPU.

No matter what I did, the result didn't change.

Here are my specs:
CPU: Ryzen 5 2400g
GPU: EVGA GeForce GTX 1070
MOBO: Gigabyte B450M DS3H V2
PSU: Corsair CX 750 Bronze
RAM: 2x 4GB HyperX @2400 MHz DDR4
Storage: 1TB HDD, 240Gb Kingston SSD

The CPU, GPU and RAMs are pretty old (can't even remember how many years). However, the motherboard is 3 months old at most, since I had to buy a new one because my previous power supply fried it.

 

[Aeacus]

One of the three, or all of following are dead: CPU, RAM, MoBo.

So, which one it actually is - for that, you need 2nd, compatible PC, where to test out components individually.

As of why any or all of them would be dead, i'd look towards your PSU.

because my previous power supply fried it.

Your current PSU isn't that much better either. CX series, at best, is mediocre quality PSU, and only good for powering office PC, without dedicated GPU. But for gaming build, especially with dedicated GPU, better quality PSU is smarter choice. E.g Seasonic Focus+ or PRIME series. Or from Corsair: RM, RMx, RMi, HX series, in 650W range.
(All 3 PCs of mine, are also powered by Seasonic. Full specs with pics in my sig.)

 

[AbsltZero]

Hi Aeacus, sorry for the late reply. I looked into what you said and started testing the components with my brother's PC.

After swapping parts around, I found that the CPU was dead. Both RAM and Motherboard are still working fine, but if I install the CPU on either computer it stops working. I've also used another CPU on my computer and it works as normal. The power supply also seems to be working fine, but as you said, I'll see about getting a more appropriate one whenever I get the chance.

Thanks for the help!