Gigabyte ga 990fx gaming socket am3 atx motherboard specifications cpu am3 socket amd am3 fx processor amd am3 phenom ii processor amd athlon ii processor please refer cpu support list for more information hyper transport bus 5200 mts chipset north bridge amd 990fx south bridge amd sb950 memory 4 x ddr3 dimm sockets supporting up to 32 gb of system memory due to a windows 32 bit operating system limitation when more than 4 gb of physical memory is installed the actual memory