4060 OC crashing left and right out of nowhere

I am dualbooting EndeavourOS and Windows. I got a Dual fan Asus RTX 4060 OC 8gb. Using a620i lighting MB.

My PC started crashing with freezing screen with occasional audio loops for 3 seconds and then it would reboot. I neither can log anything nor anything gets logged on its own to see what the issue is, on both OS. (using journalctl or eventvwr on respective OS)
I tried memtest86+, RAM is all fine.
I tried default BIOS settings and my custom low power setting, both had crashing.
I tried underclocking, still would crash.
Its not consistenly reproducible and crash can happen an hour in the start of the PC or right at the beginning.

I really dont know a way to factor out CPU or MB or PSU problem. I can try asking a friend to insert my GPU to test. but what else do others recommend and does this sound like a GPU issue to you? It just started like 4 days ago.