Random Crashes Causing Issues With Boot Order

OS: Windows 11 Home 64-bit
CPU: AMD Ryzen 7 7800X3D
GPU: GeForce RTX 5070 TI 16GB
RAM: Team T-Force Delta 32GB DDR-5 X2
SSD: WD Green 2TB M.2
Mobo: Gigabyte B850 Gaming Wifi6
PSU: Apevia 850 watt gold

I've had this computer since last September. It has done this 3 times for sure, maybe 4.

The computer will suddenly crash. The screen (one monitor) splits in half, both sides are like half pixelated for a second (I think on the bottom half of both sides), then both sides go black and have a message saying the computer needs to restart.

After restarting it will be unable to boot. If I go into the BIOS there is nothing listed under the boot order except trying to boot off the network. When I shut the computer off and turn it back on, the boot order then displays the Windows drive and I can select it and it loads like normal.

It was worrisome the first time seeing nothing to boot from and all, but now I know just to shut it off and everything is fine. But my questions are why does it happen, how can I stop it, and is it a warning sign that trouble is looming?

I don't remember the circumstances of the first crash. When the next-to-most-recent crash happened, I was right in the middle of running some pretty intensive tasks. So I thought, well, maybe I was taxing the system too much and that's what causes the crashes. But the most recent time, it crashed after I left it on overnight and it wasn't even being used. I woke up to it already in the BIOS with nothing in the boot order. So there went that theory.

Appreciate any help, thanks.