Question Having problem, not sure what is causing it.

[Odegrar]

Hello, first time posting here. I hope this is the right place to do it.


So about a month ago I started having issues with some games. While playing, my video just dies, and apparently, my computer freezes (can't really tell I have no video output to probe it). The only thing I can do is a hard reset.

My system is the following:

Asus b85Mg motherboard
Intel I5 4430 processor
2x Kingston Hyper X Fury 8gb RAM
AsRock Rx580 Phantom Gaming GPU
Gygabyte G750H PSU
Windows 10 OS
Using a 32' TV as monitor

The original setup had a different PSU and GPU when I put it together, some 5 years ago. Last year, the GPU started to show its age and I changed that and the PSU in October. I had no problems for a while. Now, last month I started having this problem where the TV loses signal while gaming and for a few seconds the computer seems to continue working (based on the sound coming from speakers) before crashing/freezing or something similar.
First time I noticed this was while playing World War Z with a friend. When the video died, I had a few seconds to tell him over Skype what had happened, before having to hard reset the whole thing. Then we moved to a different game; Green Hell. I started having the same problem there. For some reason, with games that are not as demanding I can play just fine (I guess). For example, I played several hours of Octopath Traveler with no problems. I can also use the computer for other things without having this issue.
Things I've tried so far based on what I could Google or get from my friends (who understand a little bit more than me about computers):

a) I dusted off the whole thing with compressed air
b) Checked that all power cables were correctly connected
c) I updated the BIOS to its latest version
d) I upated the AMD drivers to its latest version (clean install even used DDU to erase all possibly conflicting previous versions)
e) I updated from the old windows 7 I had to the latest windows 10 version (clean install)
f) changed the HDMI cable (just to be sure that it wasn't the cable losing signal)
g) Powered off, unpluged the case and remove the motherboard battery for a few seconds, then place it back again
h) Created a custom high performance power plan in windows that has no sleep/hibernation

Here's a short video of the issue occuring

Here you can see there's no signal but PC is still on

Apparently, nothing is overheating. I don't know if you can read the top right corner, but the GPU never reached more than 72ºC.
Curiously, I noticed that the TV loses brightness randomly. Also My RGB peripherals sometimes "blink"

Here's the mousepad blinking

According to Windows events this is going on:

Errors
Error 1
Error 2

So, according to what I can understand (googling and such) there's a power issue.
Is this correct?
If so, is there anything I can do to find what it's causing it? We're currently in lockdown here, so getting a technician to check the PC is kinda complicated.
Is the CPU/mother or anything like that dying (they're almost 6 years old after all) ?
Or do I have an issue with the more recently bought GPU/PSU (I think I could still contact the place that sold them to me to see if they're still under warranty)

I'd really appreciate any help!

 

[alceryes]

None of your OneDrive links are working.
Have you tried replugging in the aux power and reseating your GPU?

 

[Odegrar]

None of your OneDrive links are working.
Have you tried replugging in the aux power and reseating your GPU?

Sorry about the One Drive. I think the following link should work:

https://1drv.ms/u/s!Agf0Ig7I1AR-kQmO2b77JEPZITkV?e=6eDJ1n

I unplugged and replugged GPU as well as Power Cable already. I can try again, just in case, but I don't think it's gonna work.

 

[alceryes]

It's difficult to tell but I'm guessing a power supply or GPU issue.
How often does this happen? If you game, will it definitely happen within 1 hour, 4 hours, 1 day...?

Are you able to get your hands on another PSU (a good one) to hook up and test?

 

[Odegrar]

I can call my brother and ask him to bring his PC, plug my GPU to his and his PSU to mine. BUt first I gotta check that they're compatible.
BTW, this issue is kind of random. It might happen half an hour into gaming or take 2-3 hours to occur. Once I could play all day with it only happening once in 8 hours.