So, why does Vista perform better than XP Pro on an identical system, running identical software and hardware? We believe that it's down to how the operating system relates to the component hardware. When XP was written multi-core processors and multi-threaded applications did not exist. With various service packs it's been able to cope well with new technologies, but now it appears to be coming up a little short. Vista on the other hand is built with multiple cores in mind, designed to take advantage of all the latest drive speeds, RAM speeds and motherboard technology.