Asus m5a99fx pro r20 socket am3 8 channel high definition audio atx motherboard cpu amd am3 fxphenom iiathlon iisempron 100 series processors supports am3 32 nm cpu supports cpu up to 8 cores supports cpu up to 140 w amd cool n quiet technology chipset amd 990fxsb950 memory 4 x dimm max 32gb ddr3 2133oc1866160013331066 mhz ecc non ecc un buffered memory dual channel memory architecture refer to wwwasuscom for the memory qvl qualified vendors li