Which of the following platforms gives the best Solidworks performance?

Hello,

Could you please let me know which of the following platforms givesthe best Solidworks performance?

Apple MacPro (Xeon 2.8GHz 4-core) running Vista 64-bit via Bootcamp

Apple MacPro (Xeon 2.8GHz 8-core) running Vista 64-bit via Bootcamp

Apple MacPro (Xeon 3.0GHz 8-core) running Vista 64-bit via Bootcamp

PC (E8500 3.16GHz CoreDuo) running Vista 4-bit

Is more cores and RAM the faster the program runs?
Is 4GB RAM enough?

For video card, which one would you recommend?

ATI Radeon HD 2600 XT 256MB
Nvidia GeForce 8800GT 512MB
ATI Radeon HD

Thanks.SolidworksGeneral