@MadMabari Your dxdiag shows some crashes of the Nvidia graphics driver and of DirectX 9, so it's a good idea to reinstall both. For DX9, use this method:
https://answers.ea.com/t5/Technical-Issues-PC/Sims-3-launcher-won-t-open/m-p/10711778#M247861
Here's how to clean-uninstall and reinstall the graphics driver:
You can get a fresh copy of the newest Nvidia driver here:
https://www.nvidia.com/Download/driverResults.aspx/200382/en-us/
If you get more crashes after doing both of the above, please post a new dxdiag. And please do test with no mods or custom content present. If you're worried about the effects of the missing content, you can use a new save, or just not save your progress in an existing one.
Thank you for the advice, I completed the steps as indicated. I can play without any issues for twice as long as before (I don't have any mods) but it either shuts down without any error message to the desktop or it reboots the computer. EA's answer was they are aware of the problem and I should "wait" while they fix it. I'm so frustrated!
@MadMabari Software should never cause your computer to shut down or restart. Those are typically caused by hardware errors or overheating and power supply issues, respectively. Your dxdiag does list some Sims 4 crashes too, but I think it would be best to address the system issues first and then circle back to the game crashes.
For the system issues, please open Sims 4 and put it in windowed mode, but don't minimize it, and open the Task Manager to the Performance tab. Check the GPU temperature, and keep an eye on it as you play. You can move the Task Manager window so you can see that value behind the Sims 4 window; that way you won't need to keep switching back and forth. Please let me know how high the temperature gets.
Please also list the specs of your power supply: make, model, wattage, and rating for example Corsair 750W 80+ Gold. You can see the info printed on the unit itself, or probably in the order form or spec sheet that arrived with the computer if you didn't build it yourself.
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