Im just about done with my rig awaiting shipping. Specs: Athalon II X2 240 2.8ghz, (2x2gb)Crucial pc8400 ddr2 1066 mhz in dual channel,550Wpsu,1gb Diamond Hd4850,Midend biostar mobo, All on a 20 inch wide screen 1680x1050. What are the best settings I should tick and avg fps. plus Id like to know whats the max AA I can put on high without losing a good fps? If your wondering I spent $220 total(sales,rebates and Wholesale)
Well that complicates things a little.
Crysis is a case by itself.
Here is a good start with things that can be done for it.
The biggest factor that I found it to turn the shadows down to medium in that game for the biggest improvement.
Here is several links that will help.