Placement Of Components; Redundant Components And Concurrent Repair - IBM Power 780 Technical Overview And Introduction

4.1.2 Placement of components

Packaging is designed to deliver both high performance and high reliability. For example,
the reliability of electronic components is directly related to their thermal environment, that
is, large decreases in component reliability are directly correlated with relatively small
increases in temperature. POWER processor-based systems are carefully packaged to
ensure adequate cooling. Critical system components such as the POWER7 and POWER7+
processor chips are positioned on printed circuit cards so that they receive fresh air during
operation. In addition, POWER processor-based systems are built with redundant,
variable-speed fans that can automatically increase output to compensate for increased heat
in the central electronic complex.

4.1.3 Redundant components and concurrent repair

High-opportunity components, or those that most affect system availability, are protected with
redundancy and the ability to be repaired concurrently.
The use of redundant parts allows the system to remain operational:
POWER7+ cores, which include redundant bits in L1-I, L1-D, and L2 caches, and in L2
and L3 directories
Power 770 and Power 780 main memory DIMMs, which contain an extra DRAM chip for
improved redundancy
Power 770 and 780 redundant system clock and service processor for configurations with
two or more central electronics complex (CEC) drawers
Redundant and hot-swap cooling
Redundant and hot-swap power supplies
Redundant 12X loops to I/O subsystem
For maximum availability, be sure to connect power cords from the same system to two
separate power distribution units (PDUs) in the rack and to connect each PDU to independent
power sources. Deskside form factor power cords must be plugged into two independent
power sources to achieve maximum availability.
Before ordering: Check your configuration for optional redundant components before
ordering your system.
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IBM Power 770 and 780 (9117-MMD, 9179-MHD) Technical Overview and Introduction