You're definitely going to need a new graphics card at the very least, as said above Crysis 3 is DirectX 11 only. You probably also need a new CPU and more RAM for optimal performance. Crysis 3 practically needs a quad core CPU, it runs horribly on dual core CPUs, and the low clock rate on your CPU wouldn't do you many favours either. Crysis 3 is one of the most demanding games out there, and you are probably looking at a full system rebuild if you want to run it well. With a new graphics card DirectX 11 GPU (Radeon HD 7750, GTX 650 or higher, don't even bother with the extreme low end cards) you might be able to just barely get the game playable on low.