Verified answer

Since you have not given any computer specs, I am going to assume you are running with a Geforce 9 series or a Radeon 46 series. You will need to buy a better video card, have about 4-6 gigs of RAM, and you might even need a new motherboard and power supply depending on what you have at present. I would also recommend that you have at least a dual core processor. Crysis is one of the most taxing games out right now, and you will need to invest some serious money to max it out in all aspects. In fact, I would not recommend spending the $300+ dollars you will most likely have to spend in order to max Crysis out. None the less, I will link you a few parts that you will need to run at max settings.

Try High and not Ultra and leave antialiasing off, u can try max resolution then

you need to describe your rig.