Socket 939 is a PGA socket designed for desktop K8 microprocessors. The socket is primarily used with Athlon 64, Athlon 64 X2 and Athlon FX microprocessors. AMD also manufactured uni-processor single and dual-core Opteron processors for the socket 939, although these processors were just re-branded Athlon 64/64 X2 CPUs with larger level 2 cache. In addition to that small number (compared to the total number of processors for this socket) of socket 939 Sempron processors was produced for this socket.
The socket can be used with processors with internal frequencies from 1.8 GHz to 3 GHz, or with rated frequencies 3000+ - 4800+. All processors working in this socket have one HyperTransport link, dual-channel DDR memory controller, and support DDR-200 - DDR-400 unbuffered memory DIMMs.