Windows Vista Basic:
1.5 GHz or any Dual Core Processor
Integrated 64 MB Shared Graphics / 128 MB Dedicated Graphics Card
750 MB RAM
Windows Vista Home Premium / Ultimate / Business:
2 GHz or any Dual Core Processor
Dedicated 256 MB Graphics Card
1.5 GB RAM or 1.75 GB RAM if you are using Integrated 256 MB Shared Graphics
1. Windows Vista Home Premium / Ultimate / Business lags while running in 1 GB RAM due to constant memory usage of 50%+ even if there are no applications running.
2. 32-bit Operating System and Processor is recommend.