Analysts had expected Sun to begin production of the first Niagara chips - a process called "taping out" - by the end of 2003, said Kevin Krewell, editor-in-chief of The Microprocessor Report. But the August 2003 departure of Niagara's lead designer, Les Kohn, as well as a switch in the foundry used to manufacture the processors, may have set Niagara's schedule back.

VP of Sun's Scalable Systems Group, David Yen, recently said that his company expects to ship Niagara systems by the beginning of 2006 - later than the 2005 time-frame the company had predicted when it announced the Niagara processor early last year.

But Krewell said that with tape-out occurring now, it is still possible that Sun could get beta systems into customers' hands by early 2005 and ship Niagara systems by 2005.

The troubled server company recently focused more resources on its throughput computing efforts after killing off two of its planned processors: the UltraSparc V and a dual-core processor, code-named Gemini. This move is expected to accelerate the release of Niagara, Yen said.

Sun, however, is sticking to the early 2006 date for Niagara system shipments. "Right now, more than ever, we're trying to be conservative about the expectations we set," said Sabrina Guttman, a Sun spokeswoman.

Niagara is based on a concept created by Kohn's company, Afara Websystems, which Sun acquired in 2002. Designed to be a network-intensive processor with on-chip networking and security capabilities, Niagara will have eight processor cores, each of which will be capable of running four series of application instructions, called threads, simultaneously.

"It really is taking the idea of multi-core multi-threading to a much more radical approach than everybody else," said Krewell, who predicts that the chip will have appeal to users running multi-threaded Web services applications. "If you look at where Sun is targeting this part, which is Web services, it's a very thread-rich environment, and having a processor that is also thread-rich seems like a natural thing."