I have two machines on my desk, an old XP Pro and a Vista Ultimate. Even in Solitare the XP machine is far faster...
SEATTLE, Washington (AP) -- Microsoft Corp.'s operating systems run most personal computers around the globe and are a cash cow for the world's largest software maker. But you'd never confuse a Windows user with the passionate fans of Mac OS X or even the free Linux operating system.
http://www.cnn.com/2008/TECH/04/14/microsoft.xp.ap/index.html