Gmod crashing on startup

Hi. I’ve been having this problem for a couple of weeks now so I figured I’d better ask. When I launch Gmod through Steam it gets as far as the Steam launch dialogue, but then immediately crashes a few seconds later before the game even comes up on the screen. I’ve tried removing my addons, reinstalling the game, launching with -dxlevel 81 and at a smaller resolution, verifying and defragmenting the game files, repairing Steam and reinstalling Steam in a different place, to no avail. I only built this PC a few weeks ago and all of my other games, including hl2 and its episodes, work perfectly; though (as far as I can remember, and I may be wrong) I’ve not been able to get Gmod running on it at all. Here are my specs (nothing is overclocked):

Windows 7 professional 64 bit
Intel Core i5 2500K @ 3.30ghz
4GB RAM
ATI R6950 Twin Frozr II

It doesn’t create a dump file when it crashes through Steam, however running the hl2 exe located in the garrysmod folder as administrator (not sure if this is the right exe or if it’s even relevant, but I’m getting desperate here…) gave me this. Given the ‘cannot load library client’ error, I tried everything outlined here by Steam support, but that didn’t work either.

Any help would be greatly appreciated!

You aren’t supposed to run HL2.exe at all. It won’t work for reasons I don’t really know. I’m not sure how I could help you but if you have any unnecessary programs running, it might help if you close them. Also do any other source games work when you try to start them up through steam?

Yeah, it’s still the same without any other programs running. My other source games work great, though.

Bump. Anyone? :v: