I have some older TV tuner cards (like the Leadtek Winfast 2000 XP Expert) that aren't supported in the Vista Media Center. They aren't even recognized by the Vista OS as actually existing because they don't have up-to-date firmware to let itself be known. I managed to bastardize a driver to allow it to be seen to work with apps other than Media Center (which still won't recognize it). If you install XP in VP, does it see XP hardware that Vista can't? I'm still working on freeing up enough hard disk space to get VP working.