Gmod crashes on Gm_atomic

Whenever I go outside in gm_atomic, Gmod crashes immediatly. Can anyone help? It’s the usual “HL2.exe has stopped working.”

PC Specs.

Windows 7 Family Edition 64 bits
Intel Core 2 Quad CPU Q8200 2.33GHz(4 cpus)
6144MB RAM
2789 MB used, 9495 left

Ahem Graphics card and not DirectX version?

I have an ATI Radeon HD 4600 series


Does that to me on most any map, i think its some addon issue.
It doesn’t do it when i run a fresh gmod.

Ok. Thanks, I’ll delete some addons.