30 - 36 FPS, depending on whether you have AA enabled or not.
The limiting factor for Crysis with your setup will be your graphics card (rather than trying to mate a 5770 with an Intel Atom!), so it's pretty easy to predict how you'll do from the 5770 reviews - you'll be moving almost the same number of pixels as the 1920x1200 line on this graph:
I know I'll be chastised for this but that 128bit memory interface on that card will hold you back as far as Crysis goes. If you do get 30FPS you'll find it'll be choppy quite often especially at that resolution. And don't think about turning on aa. Overclocking anything will not help you here. I found a card with more than 1gig of memory to be best... nvidia.... and I have a 5850 that plays it well too. Not sure about the ice part though.
shame on you for bringing up the 128bit memory issue!
That is not an issue, the card can run crysis at playable frames if you up the CPU and GPU clocks ( NO xAA and settings on "mainstream/medium" ) . Of course there will be scenes where the card will bog down and you will notice some lag, this of course is inevitable, it happens to me as well and I play at 1680x 1050.