Crysis will make good rig swallow still! Trust me! But an DDR3 rig runs it pretty well with all GPUS that support dx 11 and above. Not the cheap models though on high res like 760, 960. They could run on lower res 720p 600p etc.
To run it perfectly is good with SLI or 780, 980, 1080 cards or RX 480, 580.