Intel's Orion

September 1996 / Reviews / Powerhouse Pentium Pro Servers / Intel's Orion

Intel designed the Pentium Pro for servers as well as desktop workstations, but it's the 82450 chip set (aka Orion), the GX version in particular, that creates Intel's server architecture. All quad-Pentium Pro servers use the 82450GX, and that explains the many design similarities between the Revolution Quad6 and t he ProLiant 5000 -- even though both ALR and Compaq designed their own system boards to get out ahead of the pack (as did Intergraph and Digital Equipment).
Specifically, the GX version of the chip set provides the error-correction-code (ECC) protection for data bus and system memory (up to 4 GB), along with parity protection on the Pentium Pro address and contro l buses. It also provides for dual, peer PCI buses, which doubles the number of PCI cards a system supports, and four-way interleaving on a 256-bit memory bus (288 bits with ECC).
It's important to configure your quad-Pentium Pro server with the correct RAM modules for two reasons. First, an 82450 bug can cause data corruption if you install certain size combinations of memory modules. Fortunately, both the ALR and Compaq BIOS programs detect problem combinations. Compaq has also gone to some length to provide a good variety of memory upgrades that all work safely. Second, if you stick in a combination of memory modules that forces the system to drop to a two-way interleave (impossible with the ProLiant 5000), the memory bandwidth drops to half at 128 bits and you take a big performance hit.

Go to next article: Testing SMP with SQL Server 6.5

Matthew Wilson
My approach to software engineering is far more pragmatic than it is theoretical--and no language better exemplifies this than C++.

more...

BYTE Digest editors every month analyze and evaluate the best articles from Information Week, EE Times, Dr. Dobb's Journal, Network Computing, Sys Admin, and dozens of other CMP publications—bringing you critical news and information about wireless communication, computer security, software development, embedded systems, and more!

Find out more

BYTE CD-ROM

NOW, on one CD-ROM, you can instantly access more than 8 years of BYTE.

The Best of BYTE
Volume 1: Programming Languages

In this issue of Best of BYTE, we bring together some of the leading programming language designers and implementors...

Copyright © 2005 CMP Media LLC, Privacy Policy, Your California Privacy rights, Terms of Service
Site comments: webmaster@byte.com
SDMG Web Sites: BYTE.com, C/C++ Users Journal, Dr. Dobb's Journal, MSDN Magazine, New Architect, SD Expo, SD Magazine, Sys Admin, The Perl Journal, UnixReview.com, Windows Developer Network