Question Why is my PC restarting randomly?

[plshelpmeomg]

For the past few weeks my PC has just begun restarting randomly (mainly when I play heavy load games like Rainbow 6: Siege, Mordhau, etc...)

I thought it was a faulty PSU because it was a cheap, off-brand, non-rated PSU and it was 2 years old already, so I bought a new one and changed it. For a few hours everything seemed fine until just now it restarted again, on its own. I don't understand what's wrong. It's connected to an extension cord as there is no close plug in the wall, and I'm wondering if that could be causing the problem? Even though I have other stuff connected to it as well such as my router and my net doesn't go down when it happens? Plus it has always been connected to an extension cord for the whole 2 years I've had this PC.

Motherboard - MSI B150A Gaming Pro
2 sticks of 4GB DDR4 2133 RAM
GTX 1070Ti 8GB VRAM
i5-6500 3.2 MHz
The new PSU is a Cooler Master Masterwatt 650W TUF Gaming Edition
Running Windows 10 on an SSD

 

[PC Tailor]

Welcome to the forums my friend!

The extension cord shouldn't be the problem if other items connected to the same one don't go down also.

Have you monitored GPU and individual core CPU temperatures under load?

 

[plshelpmeomg]

Welcome to the forums my friend!

The extension cord shouldn't be the problem if other items connected to the same one don't go down also.

Have you monitored GPU and individual core CPU temperatures under load?

I have monitored the temperatures and none of them bypass the maximum recommended/MSI Afterburner max temp settings.
Even more so, yesterday it restarted while I was playing CS:GO, despite the fact that I was playing Destiny 2 beforehand with no restarts. In Destiny the temps were higher, yet everything was fine.
All games it has restarted for me in:
CS:GO - Pretty often
Rainbow Six Siege - Very frequent
Minecraft - Not frequent, but not rare
Terraria - Same as Minecraft
Mordhau - Pretty often
Destiny 2 - I only tried once, after installing the new PSU, and it didn't restart. I haven't tried Destiny 2 on the old PSU though.

 

[clutchc]

How long is the extension cord, how many conductors (2, 3), and what gauge are the conductors? (wire size should be printed on the cable)

 

[plshelpmeomg]

How long is the extension cord, how many conductors (2, 3), and what gauge are the conductors? (wire size should be printed on the cable)

I believe it's 4 meters long. I can't find the amount or size of the conductors anywhere.

 

[plshelpmeomg]

I ran a full Avast and Malwarebytes scan, no viruses. Ran CHKDSK on my SSD, all is good. Ran RAM test, everything's fine. Checked temperatures on HWMonitor, nothing exceeds the max. I've resorted to put my GPU to 101% power in MSI Afterburner (I read somewhere that it could help? IDK), updated all my drives.
Then I ran a benchmark of the CPU for a whole hour and nothing crashed/restarted, ran a benchmark for the GPU for 30 mins and the temperature capped at 82C and nothing crashed.
Then I played Rainbow Six Siege for 90+ minutes without a restart, where-as normally after 10-20 minutes my PC would restart already, with the old PSU.
I don't even know anymore. So far so good, I guess...

 

[clutchc]

4 meters is a pretty long distance if the conductors are too small. Could be seeing occasional voltage drop to the PSU when the load gets heavy as a result. The +12v power to the card would suffer. If boosting the gfx card's power limit solved the issue, that may be enough to cover for the V drop.

 

[plshelpmeomg]

It seemed to have work until now. But now it's happening again. I'm seriously lost right now as to what it could be.

 

[clutchc]

I'm still leaning towards the extension cord being too small for its length. Your system could easily put a 300-500W load on the conductors when the system is under heavy load gaming.

Every cable should have the wire size (gauge) and number of conductors imprinted on its length. At least here is the US. If yours doesn't, the cord might not be UL approved and/or safe to use. Please check again to see if there is any specs printed along the length of the cord. Sometimes, they are spaced far apart.
Example

Are you in the US?

 

[plshelpmeomg]

I'm still leaning towards the extension cord being too small for its length. Your system could easily put a 300-500W load on the conductors when the system is under heavy load gaming.

Every cable should have the wire size (gauge) and number of conductors imprinted on its length. At least here is the US. If yours doesn't, the cord might not be UL approved and/or safe to use. Please check again to see if there is any specs printed along the length of the cord. Sometimes, they are spaced far apart.
Example

Are you in the US?

Found it, the cable says exactly as follows: "Interlink 60227 IEC 52 300/300 V PVC/PVC 70°C 2 x 0.5 SQ.MM. TIS 11 PART 5 - 2553".
I am not in the US.
Also, last night the PC restarted when I was just browsing google chrome and nothing else was going on in the background.
I just tried to reseat the GPU and both RAM sticks to see if perhaps somehow it's caused by that.

 

[clutchc]

I guess they spec out cables where you are differently than here in the US. The only thing I can make out in that string of characters is that it has a 300V max limit. Sorry, I can't help you more. I was hoping for a wire size, but even then I doubt they would use the American Wire Gauge (AWG) used here anyway.

Is there any way you can connect the system directly to the wall outlet w/o use of a long cord?