Screen margins screw up when I load gmod

I’ve recently upgraded to windows 7, and I tried to test my gmod after the upgrade. It worked, but the screen margins were about 1" smaller on either side. I’ve tried cleaning the local files, and checked it without addons, but it still reduces the screen margins.

It worked perfectly on Vista, which seems somewhat backwards to me. Thoughts?

Monitor 16:10 ? Set resolution to 16:10 etc.

It can’t. When I press apply in the graphics area of the settings, it shits its pants and doesn’t actually apply the settings.