Now that Windows Vista Service Pack 1 has made its way to testers, it's finally time to see if it delivers what the OS users have been waiting for.
While the new service pack has improved Windows Vista performance under some conditions, it also degraded it under others. Both performance losses and gains have been negligible though. The service pack, however, includes a large number of third party driver updates, so those users who didn't keep their systems up to date will feel a significant performance boost.
But file copying is a different story. Most Vista users have had troubles with its slow file copying. Windows XP utilized a cached Input/Output system which offered faster and more reliable file transfer than Vista's uncached system. Service pack 1 adds caching to Windows Vista and noticeably improves file copying operations.
On the other hand, service pack 1 is 40 to 50 percent slower than the retail version while copying from external USB 2 hard disk drives. This issue is well known and is under investigation by Microsoft right now.