I have had trouble the last 2 days with trying to get Garry’s Mod running on my machine. I have tried re-installing with a fresh copy, verifying file integrity, updating video card drivers, restarting Steam to no avail. The game will start with a 640x480 resolution with the image of the G-Man with the traffic cone and the “Loading…” dialog on the bottom right corner and nothing happens. I have tried waiting up to 15 minutes to see if time was an issue, and the game just gets stuck.
As far as the details…
Source games installed: Team Fortress 2, Left 4 Dead, Counter-Strike: Source
(Side note: On launching G-Mod, I noticed that Steam was attempting to also download Half Life 2, HL2: Ep 1, HL2: Ep 2, HL2: Deathmatch, and Portal)
Direct X version: v11 from the Windows 7 RC
No G-Mod Add-ons used or installed.
System: AMD Phenom x4 9500+ quad-core, 4GB of DDR2 RAM, Geforce GTS 250 512mb GDDR3, Windows 7 RC x64 version