A computer sales PERSONTOLD me that to UPGRADE to a 64 bit system I would have to upgrade to a 64 bit operating system... He said I can't USE Win XP since it is a 32 bit based operating system??? Do they make a different Windows for the new 64 bit motherboards and processors??Windows XP 64-bit Edition is available. http://www.microsoft.com/windowsxp/64bit/evaluation/upgrade.mspx