ZDNet have an article comparing the performance of Vista RTM and Vista SP1, and fortunately SP1 does seem to win in most cases of real world testing: [QUOTE]So, overall, real world tests show an improvement while synthetic benchmarks show a small drop in performance (I’m putting this down to drivers - and possibly even the bench software - not being SP1 ready yet). This is promising, but since this data is based on the results from a single test machine, it’s too early to declare SP1 a winner.[/QUOTE] Read the full test at [URL="http://blogs.zdnet.com/hardware/?p=1244"]ZDNet[/URL].