Pull the NVMe drive out and see if it'll boot to the boot media without that installed, just to rule a few things out.
Reset bios to default.
Remove RAM and install only 1 stick. Swap sticks if crashes continue.
When you tried to boot without the NVMe drive, was the SATA drive connected? If so, remove it as well. Make sure you're boot UEFI.
I wouldn't of thought RAM since it failed so consistently on startup like that. RAM is usually very inconsistent. But it does sound like a bad stick.
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