Here are the Need for Speed: Most Wanted system requirements (minimum)
CPU: Pentium 4 or Athlon XP
CPU SPEED: 1.4 GHz
RAM: 256 MB
OS: Windows 2000/XP
VIDEO CARD: 32 MB DirectX 9.0c compatible 3D video card (NVIDIA GeForce2 MX+ / ATI Radeon 7500+ / Intel 915+)
DIRECTX VERSION: DirectX 9.0c (included on disk)
SOUND CARD: Yes
FREE DISK SPACE: 3 GB

Need for Speed: Most Wanted Recommended Requirements
CPU: Pentium 4 or Athlon XP
CPU SPEED: 2.2 GHz
RAM: 512 MB
OS: Windows 2000/XP
VIDEO CARD: 64 MB 3D video card (NVIDIA GeForce 6200+ / ATI Radeon 9800+ )
DIRECTX VERSION: DirectX 9.0c (included on disk)
SOUND CARD: Yes
FREE DISK SPACE: 3 GB