kleox64 said:XP Pro will use a maximum of 2 physical sockets however only 4 logical processors can be used, hence a single socket quad core cpu will work. DUAL socket quad core will not, in this case you will need Server 2003 STD or above.
dual socket quad core as in 2 sockets and 8 cores (4+4) should work with
win xp fine
http://xtremesystems.org/forums/showthread.php?t=115384&page=1
unless im reading your post wrong