Intel BOXD5400XS eATX 5400 Express Chipset - Single Pack Form Factor - EATX - Extended ATX Pin Count - LGA771 Support for 45nm Intel Core2 Extreme processors in an LGA771 socket with a 1600 MHz system bus Support for both 45nm & 65nm Intel Xeon processors in an LGA771 socket with a 1600, 1333, or 1066 MHz system bus