Question PSU dead or GPU. Is doesn't make Sense. Any ideas?

[oraa22]

Hi, recently, around a week ago, my GPU started crashing under load, and yesterday crashing on windows login. I went to replace the power cable and found out, it had melted on the PSU side. I went ahead and replaced it.
Now, when I plug everything in and turn on my pc the PSU clicks and turns of again, but when I unplug my GPU it boots fine, only I can't connect a monitor, cause I don't heave CPU graphics.
While troubleshooting I tried to turn it on with my friends GPU and I got the same result, no boot.
So my question is, what is the culprit here, cause both of them work when not connected to each other.
Thx for any advice.

Thx for the advice, here is my part list (first time posting something) :
CPU: AMD Ryzen 5 5600x
CPU cooler: be quiet pure loop 240
Motherboard: aorus x570i wifi
(latest driver as of post date)
Ram: Corsair 2x16g
SSD/HDD: 2x 1t m.2
GPU: phoenix oc Rtx 3070
PSU: cooler master 850w SFX (2-3 years)
Chassis: cooler master nr 200p
OS: windows 11
Monitor: 1440p 165hz TUF gaming

Pls let me know if something is still missing

 

[Lutfij]

Welcome to the forums, newcomer!

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

I went to replace the power cable and found out, it had melted on the PSU side.
A meted connector isn't a good thing, whether it's on the GPU side or the PSU side.

While troubleshooting I tried to turn it on with my friends GPU and I got the same result, no boot.
So my question is, what is the culprit here, cause both of them work when not connected to each other.
Probable that the PSU has conked out.