Vista is bad as it is a totally different build as it's predecessor, XP. Many devices / software do not work as drivers are not created, like my dell printer, Dell did not want to make a driver for vista. However, I've read reviews somewhere that vista is able to make use of multi-cores better, ie using a multi-core built game on a quad core, XP was only able to utilize 100% on 1 core and 50% on another, the other 2 are basically idle. Vista was able to get all 4 cores running almost 100%.