Computer restarts when playing Sims 4

@mashmusen  Do you mean that you only used either the 8-pin or the 6-pin connector for the GPU, but not both?  You absolutely need to use both connectors on a graphics card like yours; I'm surprised the card would work otherwise.  Please make sure that both connectors are plugged in securely, and that you're using connectors that both say PCI Express on them, and that they're connected to the PCIe outlet on your power supply: some connectors can look equivalent, but they don't function the same.

The idle temperature on the GPU should also be much lower, although the temperature under load didn't get particularly high in the minute or two you were running the game.  Since hwinfo is picking up only one fan, please make sure all three fans on your card are spinning properly.  (It could be that there's only one sensor covering all three fans, but it's better to double-check.)

If the RAM tests don't pick anything up—please let me know what you find, and with which test(s), and whether you tested the modules separately—run hwinfo again while you play, and get another log.  It's possible the first one was simply corrupted in some way.  In case that's not what's happening though, please run Sims 4 in windowed fullscreen or windowed mode, and tab to hwinfo every couple minutes.  Check CPU and GPU temps, and let me know how they look, or you can screenshot the hwinfo window in a couple places and go back to look later.