158 IBM eX5 Implementation Guide
4.9.6 Drive combinations
The x3690 X5 drive subsystem is divided into four backplanes; each backplane can connect
to either four 2.5-inch drives or eight 1.8-inch SSDs. This section describes the supported
A configuration with four drives
Figure 4-28 shows a four-drive configuration that uses one 4x HDD backplane. This
configuration uses one SAS cable.
Figure 4-28 x3690 with one IBM 4x 2.5-inch HS SAS HDD backplane
Configurations with eight drives
Figure 4-29 shows two 4x HDD backplanes in use. This configuration requires two SAS
Figure 4-29 x3690 with two IBM 4x 2.5-inch HS SAS HDD backplanes
Figure 4-30 on page 159 shows a configuration that uses one 8x HDD backplane instead of
two 4x HDD backplanes. Two SAS cables are needed.
Firmware update and installation order:
You might need a firmware update to the ServeRAID B5015 SSD Controller if you
intermix 2.5-inch drives with 1.8-inch SSDs.
When mixing 2.5-inch backplanes and 1.8-inch backplanes, always install the 2.5-inch
backplanes to the left and all 1.8-inch backplanes to the right (as seen when facing the
front of the server).
Not all of these configurations are orderable in a configure-to-order (CTO)