Well, min reqs are listed as:

IntelŽ Core 2 Duo 2.0 GHz, Core i3 OR AMD Athlon 64 X2, or better
2 GB RAM
NVIDIAŽ GeForceŽ 7800, ATI X1800, Intel HD 3000, or better (256 MB of video RAM and shader model 3.0 or better)
25 GB available HDD space

Additionally, you can try running a systems check for the game.

There's also a wide array of options to play around with and lower in-game.