When I play some source games (Gmod and TF2 in particular), and I look at textures like brick walls or grids, I notice anti aliasing isn't working on them. I have tried SSAA (in NCP), AF, MSAA, and CSAA. Everywhere is anti-aliased except the textures. I am seeing lots of moire and it is annoying. Any help?
AA(most modern implementations) is NOT made for textures it is made for polygon edges. That would be the first problem. You may want to see if AF helps any. It is all about texture filtering if you have shimmering.
Some games with certain types of bump mapping tend to look like aliasing when it is not(well it is, but for a different reason).
FXAA may help, but it tends to have other side effects.
While SSAA(Super Sample) should help more then all others, I am not 100% sure if all games still work with it. It is also a HUGE perfromance hit to render the screen at a high resolution then re-size it. It IS still my favorite AA method since it looked great back when it was the only AA you could get, but the performance hit leaves it rarely used.
EDIt. and GRIDS, the are textures with transparent sections. Anti aliasing Transparency option(NCP) should help this. I always found that HL2's build in options worked more then well enough(and better then control panel options in many cases).