Answer Description

Socket AM3 is a 941 pin processor socket designed for AMD processors. Socket AM3 supports DDR3 memory which is it's main advantage over AM2 and AM2+.

Wikipedia

Socket AM3 is a CPU socket for AMD processors. AM3 was launched on February 9, 2009 as the successor to Socket AM2+, alongside the initial grouping of Phenom II processors designed for it. The sole principal change from AM2+ to AM3 is support for DDR3 SDRAM. The fastest CPU for socket AM3 is the Phenom II X6 1100T. Like the previous AMD socket, the "AM3 Processor Functional Data Sheet" (AMD document number 40778) has not been made publicly available. The "Family 10h AMD Phenom™ Processor Product Data Sheet" (document 446878) has, but contains only a brief list of features of the Phenom, and does not contain any substantive technical data regarding socket AM3.