Here are the Crysis System Requirements (Minimum)
CPU: Intel Pentium 4 2.8 GHz (3.2 GHz for Vista) or faster, Intel Core 2.0 GHz (2.2 GHz for Vista) or faster, AMD Athlon 2800+ (3200+ for Vista) or faster.
CPU SPEED: Intel Pentium 4 2.8 GHz (3.2 GHz for Vista) or faster, Intel Core 2.0 GHz (2.2 GHz for Vista) or faster, AMD Athlon 2800+ (3200+ for Vista) or faster.
RAM: 1 GB (Windows Vista requires 1.5GB RAM)
VIDEO CARD: NVIDIA GeForce 6800 GT or greater; ATI Radeon 9800 Pro (Radeon X800 Pro for Vista) or greater. Laptop versions of these chipsets may work but are not supported. Integrated chipsets are not supported.
TOTAL VIDEO RAM: 256 MB
PIXEL SHADER: 2.0
VERTEX SHADER: 2.0
3D: Yes
HARDWARE T&L: Yes
DIRECTX VERSION: 9.0c (included)
OS: Windows XP/Vista/7
FREE DISK SPACE: 12 GB
SOUND CARD: Yes
DVD-ROM: 8X speed DVD-ROM. This game contains technology intended to prevent copying that may conflict with some DVD-ROM, DVD-RW and virtual drives.

Crysis Recommended Requirements
CPU: Core 2 Duo 2.2 GHz/Athlon X2 4400+ or better
CPU SPEED: Core 2 Duo 2.2 GHz/Athlon X2 4400+ or better
RAM: 2 GB
VIDEO CARD: Supported chipsets: NVIDIA GeForce 8800 GTS with 640MB RAM or similar.
TOTAL VIDEO RAM: 640 MB
PIXEL SHADER: 3.0
VERTEX SHADER: 3.0
3D: Yes
HARDWARE T&L: Yes
DIRECTX VERSION: 9.0c (included)
OS: Windows XP/Vista/7
FREE DISK SPACE: 12 GB
SOUND CARD: Yes
DVD-ROM: 8X speed DVD-ROM. This game contains technology intended to prevent copying that may conflict with some DVD-ROM, DVD-RW and virtual drives.