ExtremeTech has taken a closer look at Windows Vista's first service pack. They've benchmarked it against the original Windows Vista and a Windows Vista which has been updated with a batch of hotfixes.
Prior to the coming of SP1, Microsoft released a batch of "hotfixes" for Windows Vista to tackle such issues as the ridiculously long time it takes to locally copy a folder full of files, the time remaining dialog box seeming to fall asleep at the wheel, memory allocation glitches in games and other graphical activities, and serious SLI performance issues. Maddeningly, those fixes aren't available through Windows Update; you have to manually download and install them.
What, we then asked ourselves, is the performance advantage of SP1 over simply installing the hotfixes? Will the upcoming service pack further boost Vista's power above and beyond the benefits the fixes offer over a vanilla installation of the OS? We decided to look into this question a bit further, along with plenty of synthetic and gaming benchmarks to prove it. The answers might surprise you.
You can check it out over here. Overall the service pack delivers big performance increases but the reviewer did notice that some games like Crysis give mixed results.