I've put together a four-page Ghost Recon: Advanced Warfighter Tweak Guide, based on the demo of the game. It provides the known methods of optimizing and customizing the game. Note that the demo and the retail version are essentially identical in terms of performance and tweaking, and as such download the demo and tweak it using the guide, as this will give you a genuine idea of how good the retail version will look and perform on your system. The full version of this guide will be released shortly after the retail version of GRAW is out.

TweakGuides