Unable to determine the cause of my computer crashing

Hi, here are some of the specs for my PC. let me know if you need more.

Processor: AMD Ryzen 5 5600X 6-Core Processor 3.70Ghz

RAM: 16GB

Graphics Card: AMD Radeon RX 6500 XT (4 GB)

Storage: 466GB SSD

OS: Windows 10

I primarily use my PC for gaming. The crashes happen when playing Team Fortress 2 and Final Fantasy 14, i can play other games such as Fallout 4, Civilisation 5 and Hearts of Iron 4 without issues.

When playing Team Fortress 2 my PC will crash after anywhere from 5 minutes of gameplay to 30 minutes of gameplay. About 30 seconds before the crash I can audibly hear my fans abruptly ramp up to 100%. When the PC crashes it fully turns off immediately, no bluescreen or shutting down message.

When playing Final Fantasy 14 my PC is crashing during long cutscenes or a boss fight that seems to have a lot of particle effects, though not more than I would see in other areas of the game. The crash is the same as the TF2 crash except the fans don't spin up as aggressively. I was able to delay the crash slightly by lowering my graphics settings though it would still crash all the same.

When searching through my system logs I would find errors such as 1796 (Secure boot failed to update), 6008 (previous system shutdown unexpected) and 10010 (DisruptedCOM). I didn't have any critical events during the periods the PC crashes.

My OS is fully updated as are all of my drivers. The games have both had the integrity of game files validated and had a fresh installs for good measure

It seems like it might be a hardware issue such as a power supply or graphics card but I'm relatively inexperienced with such things so was hoping someone could give some better insights. Thanks for any help, please ask if you need more info. :))