AOpen 975X is Socket M. Socket P is a different socket used by newer Meroms (Santa Rosa) and Penryn CPUs (dual and quad core). There was a big variety of different s478/479 sockets incompatible with one another.Aopen motherboards with socket 479 (Socket P) can only use Core Duo (Yonah 65nm) or Core 2 Duo (Merom 65nm) processors.