Is your PC Vista Ready?

Microsoft's Recommendation for the Minimum Hardware specs to run Windows Vista.

CPU Pentium 3/4 or Athlon Equivalent or better।
CPU Speed 800 MHZ or better
System Ram 512MB or Higher
Video Card 100% DirectX 9 graphic card capable of SVGA 800x600
DirectX Version DirectX 9.0 or better
Free Disk Space 15GB or higher
Hard Disk Capacity 20GB or higher
CD and Sound Card yes

Expert's Recommendation for the Minimum Hardware specs to run Windows Vista.

CPU Pentium 4 or Athlon Equivalent or better।
CPU Speed 1.4GHz or better
System Ram 1GB or higher
Video Card 64MB 100% DirectX 9 graphic card with Pixel Shader 2.0 hardware support
DirectX Version DirectX 9.0 or better
Free Disk Space 15GB or higher
Hard Disk Capacity 20GB or higher
CD and Sound Card yes

The easiest way to to tell if you PC is up to the task of running vista is to run CNET Vista Upgrade Advisor