Need with Gmod images/models

I started up Gmod one day and my guns were not showing completely. Parts of them are missing and along with some small parts in the map are missing or stretched. This has been pissing me off for about a month now and I can’t figure out any way to fix it. I uninstalled Gmod, deleted the file, installed it and it still doesn’t work. If I could get some help on this issue it would be greatly appreciated. There are a couple screenshots below so you can see the problem.

Seems a lot of people are having this familiar issue…

Are you running it on an integrated GPU?