http://www.techspot.com/review/379-crysis-2-performance/
This article test Crysis 2 with many GPU (from radeon HD 4850 to the last Nvidia Card), the last Sandy Bridges processor has been tested as well as old dual-core processor.
In a nutshell, this article say:
Crysis 2 may not be exactly what PC gamers expected, but despite the seemingly console-biased launch, Crytek has proven that it's still possible to create an incredibly good looking game with DirectX 9. Many new DX11-based games have shown the advantages of the newer API, but we're no longer convinced Crysis 2 suffers from its lack of DX11 -- something we never expected to say.