Bona Fide Reviews put up an article about AMDs Sockets and Cores
The s939 processors are intended to be AMD’s mid to high level processor platform as well as to bring together the s754 and s940 series processors. However, the new processor socket will not replace the 754 or 940 sockets. The 940 will continue in the server and workstation environment supporting the Opetron processor. The s754 will be home to AMD’s new value line, a cut down version, 32 bit only version of their s754 64 bit processors.AMDs Sockets and Cores
The s939 processor offers advantages over both to s754 and s940 processors. First of all, the s939 does not require registered memory as the s940 does. The use of unbuffered memory allows the memory to run slightly faster, since no buffers are being used. But, more importantly, unbuffered memory is more readily available and much cheaper.
