Intel Cranks the Clock, Ups the Cache on 32-Bit Xeon MPs

by Timothy Prickett Morgan

The third generation of 64-bit Itanium chips, code-named "Madison" and announced last Monday, was getting lots of press. But Intel also has tweaked the "Gallatin" Pentium 4 Xeon MP processors, which are used in more than 60 different 32-bit servers, with four or more processors, made by its OEM partners worldwide. And the improvement in the Gallatin's performance will, ironically, make it somewhat more difficult to justify the move to the Itanium line.

The Gallatin chips top out at a 2 GHz clock speed, and on many commercial applications (like the TPC-C online transaction processing benchmark test), chip for chip, a 2 GHz Gallatin matches the performance of a 1 GHz "McKinley" Itanium 2 processor. With Intel ratcheting up the clock speed of the Gallatin chip to 2.8 GHz, the only real performance benefit that the new 1.5 GHz Madison Itaniums will offer over new Gallatins will be on jobs that require more than the limit of 4 GB of main memory per processor, which that 32-bits imposes on servers using Intel Xeon processors. If Intel stopped making Gallatins, there would be a lot more interest in Madison. And there would probably be a lot more interest in the "Hammer" 64-bit Opteron processors, made by rival Advanced Micro Devices, which explains in part why Intel continues to improve its 32-bit server processors.

The first batch of Gallatin chips came in at 1.5 GHz/1 MB L3 cache, 1.9 GHz/1 MB L3 cache, and 2 GHz/2 MB L3 cache configurations. They sold for $1,177, $1,980, and $3,692 respectively, in 1,000-unit quantities. While the new cranked Gallatins will plug in to the same sockets as the old ones, some OEM vendors have refreshed their server lines to coincide with the new Gallatins and are encouraging customers to upgrade their servers in conjunction with moving to the new, faster processors.

The new Gallatins are based on the same 130 nanometer chip technology, and they come with either 1 MB or 2 MB of L3 cache on chip. There are three clock speeds: 2 GHz, 2.5 GHz, and 2.8 GHz. As with past server chips from Intel, only the fastest processor in the new line gets the largest on-chip cache. As was the case with the McKinley-to-Madison jump in the Itanium line, Intel is holding prices constant on the new Gallatins versus the older ones. The performance improvement on many commercial workloads normally scales with clock speed, as long as some increased L2 or L3 or cache is added. (Intel has not boosted the cache sizes on the faster Gallatins.) With the caches held constant on the Gallatins, the performance improvement should be in the range of 20 to 40 percent, and less on cache-sensitive workloads.

Intel knows that many workloads will require a larger L3 cache, which is why it will debut a Gallatin processor with 4 MB of L3 cache early next year, and the future "Potomac" version of the Pentium Xeon MP processor, due in late 2004 or early 2005, will also feature increased L3 caches. Potomac will be the first multiprocessor server chip that Intel creates using 90 nanometer and 300mm wafer chip-making technologies.

Sponsored By UNISYS/MICROSOFT

Join the escape from UNIX. The Windows Data Center is here. The revolution has begun. The Windows Data Center: The low-cost, high-performance answer to complexity. Decisions about your data center never have to be made by default again. Introducing the proven alternative to UNIX: The Windows® Data Center. Featuring the Unisys ES7000 family of servers running new Microsoft® Windows Server 2003, it's a solution that brings revolutionary performance and low-cost standardization to the enterprise like never before. With mainframe-like integrity, the ES7000 and Windows Server 2003 fully optimize today's enterprise data center. It's no wonder nearly 50% of large organizations are standardizing on Windows operating systems.(1) And by focusing solely on enabling standardized, end-to-end Windows data centers, Unisys helps generate staff efficiencies, increase agility, and mitigate risks-all while achieving greater return on technology investment. So if you've had quite enough of your inflexible data center, let us help you escape. After all, nobody wants to be on the wrong side of a revolution. For More Information Call 1-800-548-3443 or visit WeHaveTheWayOut.com © 2003 Unisys Corporation and Microsoft Corporation. Unisys is a registered trademark of Unisys Corporation. Microsoft and Windows are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries. The names of actual companies and products mentioned herein may be the trademarks of their respective owners. (1) Unisys primary market research 1Q03.