Depending on the age of the Xeons in question, they fit into a variety of slots and sockets. The first Xeons were used in a slot cartridge known as Slot 2. Any motherboard wit
…h a Slot 2 connector supports these Xeons (though due to increasing FSB speeds, they migh not operate at full speeds). The next Xeons were in a Socket 603 package. Any motherboard with a Socket 603 socket supports these Xeons (and all run at the same FSB speed). The next Xeons were in a Socket 604 package. Any motherboard with a Socket 604 socket supports these Xeons (and older Socket 603 Xeons). Due to increasing FSB speeds, the faster ones may not run at full speed on older boards). The newest Xeons are in a Socket J / LGA771 package. Any motherboard with a Socket J / LGA771 interface supports Xeons, though chipset and FSB differences may prevent newer ones from operating correctly on older boards. (MORE)