Yes, it would be the same with XP64. However, Vista x64 has the benefit of being able to use many of XP64's drivers (I'm using several right now), although XP64 may or may not have better overall legacy application support. Chances are, Vista x64 will be better supported, so I would suggest it over XP64 in most circumstances. 32-bit software works fine for both, but drivers need to be 64-bit; I would suggest seeing if there are XP64/Vista x64 drivers available for your hardware - the most likely to cause a problem are imaging drivers (printer, scanner, TV tuner, etc.).