My question was regarding whether or not I must use an opteron processor or if an athlon will work. They are pretty much the exact same, but the opterons are a good bit more expensive. Anyone have any ideas regarding this?
Also, anyone happen to have a few? I am currently in need of 4 socket 939 processors, and lots of DDR-400 RAM
I also saw some server supply companies selling HP opteron 185 processors. Are these processors the same or is there some underlying architecture difference?
It is important to remember that the Athlon 64 cannot support more than 1 processor/motherboard. The Opterons support as many CPUs as there are sockets in a single motherboard.
That's not quite true. Athlon 64s and all of the rest of AMD's desktop CPUs made in the last 10 years do only support one processor per motherboard. However, quite a few Opterons only support single-socket operation as well. The Opteron 100-series and 1000-series units (such as the Socket 939 Opteron 185) only support single-socket operation. Except for the very first generation of Opteron 100s, the single-socket Opterons have been put in different sockets than the multi-socket-capable units, generally in the same socket as desktop CPUs.
Also, not all Opterons will support as many sockets as there are in the motherboard. The Opteron 200 and 2000 series only support up to 2-CPU configurations but will fit in motherboards with 4 or 8 sockets designed for the 8-CPU-capable Opteron 800 or 8000 series. Currently what you say is true as there are no new single-socket-only Opterons as the dual-CPU ones are inexpensive enough and the dual-CPU-only units (Opteron 4000 series on Socket C32) will not fit in motherboards for four-CPU-capable units (Opteron 6000 series on Socket G34.) But that was not always the case.