Okay lets do this

[LiNuX]

Yeah, it's an on board GPU. That's probably why you're having issues. The 9100 isn't that high end. It might not be the GPU overheating, most likely it just can't handle games anymore so it stutters. Finding a replacement might do it.

But I'm mostly speculating the causes of the issue. Can't test any of your parts so I can't be certain on any of it because it could be so many things.

You can also get Everest Home Edition to look at the temperature if speedfan doesn't suit. Here is a link: |MG| EVEREST Free Edition 2.20 Download