IBM Power 750 Technical Overview And Introduction page 98

Table 2-24 lists the SAS ports associated to the disk bays with the mode selector switch 4.
Table 2-24 SAS connection mappings using mode switch 4
SAS connector location code
P4-T1
P4-T2
P4-T3
P4-T4
For more detailed information about cabling and other switch modes, see the Power Systems
Enclosures and expansion units documentation:
http://pic.dhe.ibm.com/infocenter/powersys/v3r1m5/topic/ipham/ipham.pdf
General rule for the 12X I/O drawer configuration
To optimize performance and distribute workload, use as many multiple GX++ buses as
possible. Figure 2-22 shows several examples of a 12X I/O drawer configuration for the
Power 750 and Power 760 servers:
Figure 2-22 12X IO Drawer configuration
12X I/O Drawer PCIe loop
The I/O drawers are connected to the adapters in the Power 750 and Power 760 system
unit with data transfer cables such as the 12X DDR cables for the FC 5802 and FC 5877
I/O drawers.
The first 12X I/O drawer that is attached in any I/O drawer loop requires two data transfer
cables. Each additional drawer, up to the maximum allowed in the loop, requires one
additional data transfer cable. Consider the following information:
A 12X I/O loop starts at a system unit adapter port 0 and attaches to port 0 of an I/O
drawer.
The I/O drawer attaches from port 1 of the current unit to port 0 of the next I/O drawer.
Port 1 of the last I/O drawer on the 12X I/O loop connects to port 1 of the system unit
adapter to complete the loop.
84
IBM Power 750 and 760 Technical Overview and Introduction
750
760
PCIe
One PCIe I/O Drawer
PCIe
750
760
PCIe
Two PCIe I/O Drawers
Mappings
P3-D1 to P3-D5
P3-D6 to P3-D9
P3-D10 to P3-D14
P3-D15 to P3-D18
750
760
Three PCIe I/O Drawer
750
760
Four PCIe I/O Drawer
Number of bays
5 bays
4 bays
5 bays
4 bays
PCIe
PCIe
PCIe
PCIe
PCIe
PCIe
PCIe