Nvidia have just put up a rather informative ‘Graphics and Performance Guide’ for GTA 5 on PC, providing pretty in-depth analysis of each graphics setting.
It’s useful for AMD users too, since while it obviously covers the special Nvidia effects like TXAA, it also has plenty to say about ‘neutral’ factors like draw distance and depth of field effects.
The piece starts by explaining the benchmarking process (not easy in GTA 5, due to how variable the world is) and then takes each graphical setting one by one to discuss how they’re applied, and the relative performance impact. There are some interesting side-notes too, such as this about the game’s ambient occlusion: “In Grand Theft Auto V though, no AO shadows are to be found because of a game application bug. Expect it to be fixed in a forthcoming update.”
Each of GTA 5’s graphics settings are presented with helpful comparison pictures, so you can see how (for example) 16x anisotropic filtering compares to using no AF at all.
If you’re still juggling various combinations of settings and trying to get GTA 5 looking as fine as possible, while also running at a steady frame-rate, it’s worth a read.
Earlier today, Rockstar released a new PC patch for GTA 5, so that may help a little too.