Here’s a tip to speed up Windows Vista and Windows 7 boot times on a multiple-core CPU PC by instructing the OS to use all cores during startup. The setting is part of Msconfig.exe utility. On the Boot tab, click Advanced Options button and then select the Number of Processors check box to see the settings (if you look in the Windows XP (KB 833721) version of Msconfig, you’ll see a similar setting on the BOOT.INI tab, which sets the /NUMPROC switch – same thing).
Tip: To use all of the CPU cores on a Windows PC, just install Windows. You don’t need to adjust any other settings.
Source:→ Ed Bott