Windows Vista has a prefetcher feature that allocates resources for a faster launch of applications and boot.Windows 7 the upcoming OS from Microsoft, has better startup timing than Vista, but incase you find it sluggish you can try this registry hack for a faster startup.

This hack makes prefetcher focuses on the booting process instead of both booting and application launch prefetching,allocating more resources for startup prefetching.

1. Click Start.
2. Go to the Search programs and files textbox, type regedit.
3. Click Regedit.exe
4. If the UAC window appears, click Yes.
5. In the registry, locate this subkey: HLKM\ SYSTEM\CurrentControlSet\ Control\SessionManager\MemoryManagement\ PrefetchParameters.
6. In the right pane, double-click EnablePrefetcher.
7. Change the value to 2 and click OK.
8. In the right pane, double-click EnableSuperfetch,.
9. Change the value to 2 and click OK.
10. Exit the registry and restart your computer for the changes to take effect.

Note : If you want to change the settings back to their default values, repeat the above steps, but change EnablePrefetcher and EnableSuperfetch to 3.

[Via - WebTlk]