In-Game Problem

Hub is missing parts.
Same with the -menu(Q menu) and normal menu problems.
Clean re-install did not help. Fresh install, no addons
-Intel Centrino 2 Duo @ 2.0
-Ati Radeon HD 2600 512MB DDR3
-4GD DDR2 Ram
-Windows Vista 64-Bit (SP-1)

This is the problem looks like-

sorry to say this dude but…your gmod is fucked up dude…get a new grapx card

everyone always says “new video card”
its not the card.
if it can run gta 4, i think it can run gmod. And if a ati 9800 pro can run, the ati 2600 hd kills that card.

It may not be the card, and I can understand buying a new video card would not be an option available to everyone, but try updating the drivers if you haven’t got the latest version. The latest ones for your card are here