Sun Microsystems looks poised to lead the “mainstream” multi-core race for at least a couple more years. By late 2009, the server maker should deliver a third major revision of its Niagara processor which will have 16 cores and an astonishing 16 threads per core, The Register has learned.

Today, Sun sells an eight-core “Niagara” chip that can handle eight software threads per core. Customers can fit two of these UltraSPARC T2 chips, as they’re officially called, into a server, providing up to 128 threads in a 1U system. Soon enough, Sun will also sell a four-socket system code-named Botaka.

We’ve confirmed that Sun is looking to push the UltraSPARC Tx line to even greater heights with a 16-core, 16-thread per core eight-socket server. So, each socket is chewing through an insane 256 threads. And the eight-socket box will do 2,048 threads.