Re: Sims 4 makes my computer restart itself

@AngryChicken028  That worked fine.  It's a bit easier if you upload the file itself, but in this case, all I had to do was copy the raw paste info, paste it into a Notepad document, save it as a .csv file, and the log reader opened it as normal.  If you're curious, Excel should open it too, although not in as convenient a format.

Anyway, there's an obvious issue that would explain the crashes: the power supply isn't delivering anywhere near 12 volts once your system is under load, i.e. once you launch whichever game generated this log.  The log doesn't have a separate reading for the PSU's 12 V rail, but you can still see the effect on the graphics card.  This is the voltage reading from the 6-pin connector plugged into the card:

And this is from the PCIe slot where the GPU is installed:

In both cases, the timing of the drop coincides perfectly with the graphics card's load increasing, as in, when it starts rendering a game rather than just your desktop.

The very low voltage alone would explain both the restarts and why your system does fine when you disable the card: the integrated graphics chip that takes over when there's no dedicated card is part of the processor, and as such it's not drawing from the 12 volt rail.  As for the GPU, anything lower than 11.9 V can explain restarts or other serious system issues.  And as you can see, even when your system is idle, the power supply is mostly not even delivering that.

The point is, it looks like you need a new PSU.  The fact that the voltage is low both from the motherboard's PCIe slot and the supplementary connector suggests strongly that this is an issue neither of the cables themselves nor of how they're connected but rather the PSU itself.  If you want to be thorough before spending money though, you can try borrowing a power supply from a friend or family member.  A 400W PSU should be sufficient both for testing and as a potential replacement.