IBM Power 750 Express Hardware Announcement page 41

7031-D24 24
7031-T24 24
7214-1U2 1
7314-G30 8
I/O drawers are connected to the adapters in the CEC with the following cables:
• Data transfer cables:
– 12X DDR cables for the feature 5802 and 5877 I/O drawers
– 12X SDR or DDR cables for the feature 5796 and 7314-G30 I/O drawers
• Power control cables
12X I/O drawer cable connections are always made in loops to help protect against
a single point-of-failure resulting from an open, missing, or disconnected cable. A
system with nonlooped configurations could experience degraded performance and
serviceability. If a nonloop connection is detected, a problem is reported.
The first 12X I/O drawer attached in any I/O drawer loop requires two data transfer
cables. Each additional drawer in the loop (up to the maximum allowed) requires
one additional data transfer cable.
The first 12X I/O drawer attached to a system unit requires two power control
cables. Each additional I/O drawer added to a system requires one additional power
control cable. Each system has one power control loop. All I/O drawers attached to
a system are included in the same power control loop. Power control cable loops are
different in this regard from data transfer cable loops.
Dual-Port 12X Adapter Options
Dual-Port 12X Channel Attach Adapter (#6446): Use the short run adapter for
feature 5796 or 7314-G30 expansion I/O drawers located in close proximity to the
host system or to other drawers in the I/O expansion loop. This adapter does not
include signal repeaters.
Dual-Port 12X Channel Attach Adapter (#6457): Use the long run adapter for
feature 5796 or 7314-G30 expansion I/O drawers located farther from the host
system or other I/O drawers in the I/O expansion loop. This adapter includes signal
repeaters to accommodate the longer cable lengths.
12X Cable Choice
Each feature 5796 or 7314-G30 12X drawer requires one Dual-Port 12X Channel
Adapter, either Short Run (#6446) or Long Run (#6457). The choice of adapters is
dependent on the distance to the next 12X Channel connection in the loop, either to
another I/O drawer or the system unit. The following table identifies the supported
cable lengths for each 12X Channel adapter. I/O drawers containing the Short Run
adapter can be mixed in a single loop with I/O drawers containing the Long Run
adapter. In this table, a "Yes" indicates that the 12X cable identified in that column
can be used to connect the drawer configuration identified to the left. A "No" means
it cannot be used. The 12X DDR or SDR cables can be used with the feature 5796 or
7314-G30.
12X DDR
5796 to 5796 w/12X
Short Run adapter
(#6446) in both
drawers
5796 w/ 12X Short
Run adapter (#6446)
IBM United States Hardware Announcement
110-009
24 24
24 24
1 6
8 8
12X Cable Options
0.6 M 1.5 M
(#1829)(1)(#1830)(1)(#1840)(2) (#1834)(3)
(#1861)(1)(#1862)(1)(#1865)(2) (#1864)(3)
Yes Yes
3.0 M 8.0 M
No No
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