Document

This Technical Advisory describes an issue which may or may not affect the customer’s product
Technical Advisory TA 719-02
5200 NE Elam Young Parkway
Hillsboro, OR 97124
October 27, 2004
Copyright © 2004 Intel Corporation. * Other names and brands may be claimed as the property of others.
Intel® Server Board SE7221BK1-E and Intel® Server Platform SR1425BK1-E
Available memory limitation when 4 GB installed
Information in this document is provided in connection with Intel products. No license, express or implied, by estoppel or otherwise,
to any intellectual property rights is granted by this document. Except as provided in Intel's Terms and Conditions of Sale for such
products, Intel assumes no liability whatsoever, and Intel disclaims any express or implied warranty, relating to sale and/or use of
Intel products including liability or warranties relating to fitness for a particular purpose, merchantability, or infringement of any patent,
copyright or other intellectual property right. Intel products are not intended for use in medical, life saving, or life sustaining
applications. Intel may make changes to specifications and product descriptions at any time, without notice. The Intel Server Board
SE7221BK1-E and Intel Server Platform SE1425BK1-E may contain design defects or errors known as errata which may cause the
product to deviate from published specifications. Current characterized errata are available on request.
Products Affected
Product Product Codes
SE7221BK1 BBKBB
SE7221BK1LX BBKBBLX, SC78048
SR1425BK1
Description
When the Intel
®
E7221 chipset is populated to its maximum memory capacity of 4 GB (Giga Bytes), the Operating
System (OS) may report a significantly lower amount of available memory. This is only an issue when the maximum
memory capacity of 4 GB is used with the Intel Server Board SE7221BK1-E.
Root Cause
System Resources require addressing which overlaps physical memory below 4 GB:
– System BIOS
– Motherboard Resources (I/O APIC)
– Memory Mapped I/O
– PCI Express* Configuration Space
– Additional PCI Device Memory
– VGA Memory (Video aperture)
– Other chipset and system devices
These requirements may reduce the addressable memory space available to and reported by the Operating System.
These memory ranges, while unavailable to the OS, are still being utilized by subsystems such as I/O, PCI Express and
Integrated Graphics and are critical to the proper functioning of the server.
Use of Available memory below 4 GB by system resources is not specific to Intel chipsets, but rather a limitation of
existing PC architectures and current limitations of some 32-bit operating systems. Some 32-bit operating systems may
not be capable of recognizing greater than 2 GB of memory. This issue potentially impacts any chipset with 4GB
maximum memory configuration.
Intel has addressed this from a hardware perspective in future platforms, anticipating that future Operating Systems will
provide greater than 4 GB of memory support.