Today, at the CeBIT 2002 technology trade show in Hannover, Germany, Intel introduced Xeon MP, the server microprocessor previously known as Foster. In Intel's Xeon line of workstation and server chips, this is the third to use the company's NetBurst architecture, (which debuted in early 2001 with the Pentium 4 desktop CPU). But this is the first Intel IA-32 processor to offer three levels of on-chip cache, according to Lisa Hambrick, Intel's director of enterprise processor marketing.

As the MP in its name implies, Xeon MP is intended for multiprocessor servers—in this case, machines requiring four, eight, or more chips—but, through Intel's hyperthreading technology, a single MP chip can, in certain cases, mimic the behavior of multiple CPUs. Intel believes the chip's design will significantly improve on the performance of the company's existing server chips. "If you simply increase a chip's clock speed from, say, 700 up to 900 MHz, you get a performance increase of 5, 7, maybe 10 percent," said Hambrick. "But when you do change to a new micro-architecture, as we've done with Xeon MP, usually you get a much bigger jump."

When Intel's Xeon line debuted in 1998, it used essentially the same core architecture as the Pentium II, then the company's leading desktop processor, but offered larger caches and a few other innovations designed specifically for servers and workstations. Xeon chips based on the Pentium III arrived in 1999, and they helped Intel dominate the server CPU market over the following two years. According to research firm International Data Corp. (IDC), Intel supplies the chips for 70 percent of all single- and dual-processor systems and for 67 percent of systems with four processors or more.

Last year, Intel incorporated the Pentium 4's NetBurst architecture, dubbing the line of CPUs "Xeon for Workstations". When it first arrived on the scene, NetBurst—offering a 400-MHz bus, new pipeline and cache technologies, and SSE2 (an update to Intel's SSE multimedia instruction set)—didn't provide much of an improvement over Pentium III architecture. A year later, though, with IA-32 clock speeds at unprecedented levels, the newer technology has completely eclipsed the Pentium III.

Other than being able to manage temperatures, voltages, and the like, Xeon for Workstations was little different from the desktop version of the Pentium 4. The Xeon line has undergone a much greater change in the past two weeks. First, on February 25, Intel introduced the chip it had long referred to as Prestonia. Now known simply as Xeon, this chip is intended for single- and dual-processor servers. Manufactured on Intel's 0.13-micron process, the CPU offers 512K of level two cache and is available at clock speeds of 1.8, 2, and 2.2 GHz.

More importantly, however, Prestonia was the first chip to use hyperthreading and the first to be paired with Intel's new server chipset, known as the E7500. When running a multithreaded application, the chip can, in effect, behave like multiple chips. "It makes a single processor look like two logical processors," says Shannon Poulin, Intel's enterprise marketing manager. "The chip's performance isn't quite as good as two physical processors, but it's still an improvement."

Once-codenamed Plumas, the E7500 chipset includes the new 64-bit PCI bus technology, PCI-X, and it's the first Intel server chipset that's compatible with double data rate (DDR) memory, the memory technology that gained notoriety when Intel competitor AMD began supporting it. DDR, significantly faster than SDRAM memory but only marginally more expensive, has been paired with the Pentium 4 since the beginning of this year.

In many respects, the Xeon MP (the former Foster) isn't that different from the Xeon (the former Prestonia). It's manufactured on Intel's 0.13-micron process, uses the NetBurst architecture, and is compatible with the E7500 chipset. Yet the Xeon MP is intended not for one- and two-way servers, and it offers up to 1MB of level three cache.

Intel is already shipping the Xeon XP at clock speeds of 1.4, 1.5, and 1.6 GHz, and over the next two weeks, several of the leading server manufacturers, including Compaq, Dell, IBM, and HP, are expected to announce systems that use the new chip. Others will follow later in the spring.