AMD desktop socket options
A crash course guide to AMD’s desktop socket options
If you’ve shopped around for a modern AMD processor, you know that there are a range of chipsets floating around depending on which generation you want. Bulldozer, Piledriver, and Llano all need a socket to fit in, so which do you need for your new system?
If you’re running an AMD desktop system, chances are good that you have a motherboard with the AMD AM3 socket.
Released in February 2009 alongside the first generation of Phenom II processors, AM3 brought DDR3 support to AMD chipsets for the first time. This broke backwards compatibility with previous CPUs which could only function on DDR2 motherboards, and featured a new 941 pin socket layout as opposed to the previous 940 pin socket layout of AM2/2+.
AM3 CPUs could work with previous generation AM2/2+ sockets and chipsets however, creating an affordable upgrade path for those who couldn’t fork out for a new CPU, motherboard, and RAM.
The high-end AM3 boards support AMD CrossfireX technology, as well as SATA III 6Gbps, dual channel DDR3, and the PCIe 2.0 specification.
AMD improved the original AM3 socket with AM3+, released alongside CPUs based on the redesigned Bulldozer architecture.
This new socket came with a 942 pin layout as opposed to 941 on AM3, however this did not break socket compatibility with processors. AM3 processors would work on AM3+ motherboards without any modification necessary. However, for the reverse, AM3 motherboards needed a BIOS update to support AM3+ processors.
Improvements over AM3 include a faster serial link between the CPU and power controller (3,400MHz as opposed to just 400MHz on AM3), improved power regulation, and a far higher maximum current support of 145A rather than 110A. This allows better over-clocking and greater stability at higher voltages.
Finally, a redesigned cooler retention bracket improved CPU airflow, while retaining backwards compatibility with older coolers.
July 2011 saw the release of socket FM1, designed for use with AMD’s mainstream fusion processors.
Higher end FM1 chipsets include USB 3.0 support, SATA III 6Gbps, a 65nm fabrication process, and HD audio support.
Socket FM1 will be replaced by FM2 later in 2012 when the AMD Trinity desktop parts are released.