"PC World’s in-house tests with the RTM version of Vista SP1 have shown mixed results. In file copying tests, the service pack proved noticeably faster than the original Vista OS. Other tests, on the other hand, showed little improvement (or actually performed worse than Vista without the service pack). For instance, our preliminary file compression tests showed a decrease in performance with SP1 installed.
Overall, we found Microsoft’s claims of dramatic performance enhancements to be somewhat overstated. PC World continues to evaluate the performance impact of Vista SP1, and more test results will be forthcoming.
Microsoft promises performance and power consumption improvements in many aspects of the Vista user experience, including better performance while browsing network file shares, improved power consumption, faster loading of large images, and faster searches." – Content courtesy of Windows Vista SP1 available now — do you need it? | InfoWorld | News | 2008-03-18 | By Robert Strohmeyer, PC World