RealTime IT News

Intel Planning Six-Core Xeon Processor

Someone at Sun Microsystems is going to get spanked, and Intel is holding the paddle.

A PDF document from Sun's Austrian offices found its way onto the external Sun network and was immediately grabbed by visitors. Sun removed the offending file but once something gets on the Internet it's impossible to contain.

The document outlines the partnership between the two companies, which is about a year old. While undated, it has pricing information from November 2007. There are very few revelations in the document, except for the page with details on Dunnington, a new high-end Xeon for multiprocessor servers.

Dunnington will be the successor to Tigerton, which has been on the market for less than a year. The Dunnington processor, which Intel has heretofore not detailed, would reportedly be a six-core design built on Intel's 45nm Penryn architecture, three L2 caches with each core pair and a unifying 16MB L3 cache.

[cob:Related_Articles]It would also have the same 40-bit physical addressing and be pin-compatible with Tigerton servers and work with the Clarksboro chipset that is used in Tigerton servers. The PDF foil said it would target "rack-optimized & ultra-dense SKUs."

Intel declined to comment on the contents of the PDF file.

Three L2 caches and six cores would seem to mean three dual core processors on one die, similar to the current quad-core Xeons, which are two dual core packages on one physical unit. Analysts seem to agree with that design, and think the unifying L3 cache will make a big difference.

"This has the potential to be a dramatically better product than Tigerton and the Harpertown product it replaces," said Nathan Brookwood, research fellow with Insight64. "Yes, it looks like three dual cores on one die, but instead of the kludgey stuff in the past where the only interface was the front-side bus, here all three dual cores can talk to a shared L3 cache."

There had been some rumors of an eight-core design for Dunnington. Tony Massimini, chief of technology for Semico Research, thinks the six-core design was the best design choice on a number of levels.

"One reason I can think of is for pricing," he said. "If you were to do this as a monolithic eight core chip, it would probably be too expensive. I can see how this would be something in between." He also added that it was probably the best design when it came to affordable yields, and that an eight-core design might not be the best choice financially.

The slide for Nehalem, Intel's next-generation design due in the second half of the year, didn't reveal anything new but confirmed what is already known: two, four and eight core designs with the return of HyperThreading technology, first introduced in the Pentium 4 in 2000.

Each core will support up to two threads, so Nehalem processors will support between four and 16 threads. It will also feature Intel's new QuickPath architecture, integrated memory controller and an optional integrated graphics controller.

When Nehalem ships later this year, it's expected to be available only in two processor designs. Four socket Nehalem will appear in 2009, so until then, Dunnington will be the four-socket solution. "Dunnington is an easier transition for OEMs and users and should provide a pretty respectable improvement in performance," said Brookwood.