Reliability; Designed For Reliability - IBM Power 720 Overview

4.1 Reliability

Highly reliable systems are built with highly reliable components. On IBM POWER
processor-based systems, this basic principle is expanded upon with a clear design for
reliability architecture and methodology. A concentrated, systematic, architecture-based
approach is designed to improve overall system reliability with each successive generation of
system offerings.

4.1.1 Designed for reliability

Systems designed with fewer components and interconnects have fewer opportunities to fail.
Simple design choices such as integrating processor cores on a single POWER chip can
dramatically reduce the opportunity for system failures. In this case, an 8-core server can
include one quarter as many processor chips (and chip socket interfaces) as with a dual core
processor design. Not only does this case reduce the total number of system components, it
reduces the total amount of heat generated in the design, resulting in an additional reduction
in required power and cooling components. POWER7+ processor-based servers also
integrate L3 cache into the processor chip for a higher integration of parts.
Parts selection also plays a critical role in overall system reliability. IBM uses three grades of
components; grade 3 is defined as industry standard ("off-the-shelf" components). As shown
in Figure 4-1, using stringent design criteria and an extensive testing program, the IBM
manufacturing team can produce grade 1 components that are expected to be 10 times more
reliable than industry standard. Engineers select grade 1 parts for the most critical system
components. Newly introduced organic packaging technologies, rated grade 5, achieve the
same reliability as grade 1 parts.
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0.6
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Figure 4-1 Component failure rates
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IBM Power 720 and 740 Technical Overview and Introduction
Component failure rates
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Grade 3 Grade 1 Grade 5