Question Graphic card burnt as soon as PC turned on, How to check PCIe working or not.

Aug 10, 2021
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0
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PC Specs :
i7 10700F
16gb DDR4 Ram
MSI Mortar B460M wifi
Gigabyte 750w PSU(Gold)
GTX 650
1TB SSD+2TB HDD
Hey Guys,
So, I turned on my PC and it started rebooting very fast, till the time I switch it off from its main it gave a fire for a second and the fire was stopped, I quickly turned my main off and I saw my GPU left side 3 pins were burnt, the PCIe slot is also burnt from the outer area, I don't know whether it is working or not, the GPU I had plugged into the PC at that time was my old GTX 650 so it does not bother me if my GPU is not working cause I was about to buy a new one.
I can't figure this out, Is this the problem with of GPU or motherboard?
My motherboard is in warranty so I can claim the warranty if my PCIe is damaged.
How can I test that my PCIe slot is working or not? (Without risking another GPU)
I am attaching the pics. (The black portion shown on the motherboard is cleanable with Isopropyl alcohol)
Let me know what should I do

NOTE: The first pic is of just after the incidence hence the PCIe slot looks burned (black)....... the second image is after cleaning it with ISO Propyl Alcohol

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