Intel is shipping an updated version of its dual-core Itanium 2 server processor, called Montvale. But don't expect to see a dramatic improvement in performance from the new chips, despite the addition of several new features.

Made using the same 90-nanometer (nm) process technology used to produce the existing Itanium 2 9000 series of processors, Montvale -- formally known as the Itanium 2 9100-series chips -- offers incremental improvements, including a faster front-side bus on some models and features that lower power consumption in certain situations and improve reliability.

"Essentially, this is a follow-on product to the current one," said Eddie Toh, regional platforms marketing manager in Intel Asia-Pacific's Server Platforms Group.

Itanium 2 processors are designed for high-end servers mainly used in specialized applications, such as finance and banking.

Some 9100 models run at slightly higher clock speeds than their predecessors but offer the same amount of on-chip cache. For example, the high-end 9150M runs at 1.66GHz, uses a 667MHz front-side bus, and has 24MB of cache, while the older 9050 runs at 1.6GHz, uses a 533MHz front-side bus, and sports 24MB of cache. Both chips will be available for $3,692 in 1,000-unit quantities, a standard pricing method for processors, Intel said.

The faster front-side bus and higher clock speeds in the 9100 series still offer respectable performance gains of around 19 percent over the 9000 series, Toh said, citing the results of testing done by Intel. The 9100 models that offer the higher models include an "M" alongside their model numbers to differentiate them from those using the slower 533MHz clock speed, which carry an "N."

The main differences between the 9000 and 9100 series lie in a couple of new features incorporated in the 9100 series. The Core Level Lock Step feature included in the new chips is intended to improve reliability by detecting and eliminating errors in the processor cores, keeping calculation results consistent between different cores -- a reliability feature that already exists for maintaining consistency between processors. Some 9100 models also use a Demand-Based Switching feature that helps lower power consumption when utilization levels are low.

The differences between the 9000 and 9100 series are less obvious with models at the lower end of the lineup. For example, the 9120N runs at 1.42GHz, uses a 533MHz front-side bus, and has 12MB of cache; the same as its predecessor, the 9020. The 9120N does not have demand-based switching feature, but the chip does incorporate the Core Level Lock Step feature. The 9120N is priced at $910 in 1,000-unit quantities, Intel said.

Beyond Montvale, Intel is working on three future versions of Itanium. Tukwila, which will be manufactured using a 65-nm process and pack four processor cores on a single silicon die, will be released next year, Toh said. Tukwila will be followed by Poulson, a 32nm chip that uses a new processor microarchitecture, and then a chip called Kittson.