®
SG24-6947-01 ISBN
Draft Document for Review April 7, 2004 6:16 pm

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TECHNICAL

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BUILDING TECHNICAL
INFORMATION BASED ON
PRACTICAL EXPERIENCE
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IBM eServer zSeries 990Technical Guide
Structure and design -
A scalable
Processor Unit,
Memory, Multiple
Capacity upgrade
options
The IBM Eserver zSeries® 990 scalable server provides major
extensions to existing zSeries architecture and capabilities. The
concept of Logical Channel Subsystems is added, and the
maximum number of processor units and logical partitions is
increased. These extensions provide the base for much larger
zSeries servers.
This IBM® Redbook is intended for IBM systems engineers,
consultants, and customers who need to understand the zSeries
990 features, functions, availability, and services.
This publication is part of a series. For a complete understanding
of the z990 scalable server capabilities, also refer to our
companion redbooks:
IBM Eserver zSeries 990 Technical Introduction, SG24-6863
IBM Eserver zSeries Connectivity Handbook, SG24-5444
Note that the information in this book includes features and
functions announced on April 7, 2004, and that certain
functionality is not available until hardware Driver Level 55 is
installed on the z990 server.

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