black screen's solution is just the same as mentioned in another thread, clock down you graphic card to stock NOT factory clock. My gtx570's factory clock was 800/1600/2000, black screen occurs all the time. after i clock down it to 732/1464/1900 which is nvidia's reference design, the game runs smoothly as silk.

the crash after loading on my system was caused by insufficient memory, though i have 6g memory and x64 to let the game lavish. the reason is my system is a little bit special. for the 6g memory, 2g are allocated as ramdisk, up to 1.5g pagefile is stored in the 2g ramdisk, and no virtual mem on my physical hard drive, usually, this config could utilize my ram usage, in crysis 2 case, only ends with crash.

anyone who disables his virtual memory may suffer this issue as well. my solution is simple, put another 6g virtual memory on physical harddrive, shrink my ramdisk to 1g, so 5g memory is usable for crysis 2.
===================how to run hi-res & dx11 in 32bit win7 ===================
i check crysis2's largeaddressaware flag, its turned on, which means:

in x64, crysis2.exe which is a 32bit executable can allocate up to 4G memory discarding 32bit windows 2G limit. and it also means if you insisting using 32bit windows 7, you can enable PAE and use AWE to let single process access more the 2g memory which can lead to similar effect running crysis2 on x64. you can find more about how to use PAE and AWE on google to unlock single process memory limit. however, doing this means hacking windows, and only try this if you have >=6G memory because you are squeezing memory from system kernel. if you has only has 4g memory, system may very easily crash.

you may find more on:
http://us.battle.net/wow/en/forum/topic/1658706617?page=6
WOW suffers insufficient memory as well.
USE AT YOUR OWN RISK and SAVE YOUR WORK BEFORE RUNNING THE GAME