@RogueRageArts It would be helpful to see whether this is a heat-related issue. Please download hwinfo from here:
https://www.hwinfo.com/download/
You don't need to install anything; just choose the Portable version, unzip it, and launch it from Downloads or wherever you like. If you do want the full installer, be sure to click the button for hwinfo itself, not for lansweeper.
Restart your computer, open hwinfo, choose Sensors Only, and leave it running. Then try to play Sims 4, first on the iGPU. Once the game crashes, check the maximum temperatures for anything processor-related, or the integrated graphics if it's listed separately. Hwinfo does list a lot of info, but you can ignore anything that's not temperature-related.
Next, repeat the test but with the game using the dedicated card (you can set it to high-performance). This time, check the temps for the dedicated card, which will have its own section towards the bottom of the screen. Let me know what you find.
The useful thing about hwinfo is that it lists the maximum values for each entry during the time hwinfo itself was open. Silicon cools quickly, so you might not catch an overheating issue if you wait until the game has crashed, but you should at least see how hot your hardware was before the crash.