Internal storage

The server can support up to 16x 2.5-inch drives, up to 32x 1.8-inch drives, or a combination of both
2.5-inch and 1.8-inch hot-swap drives, using the supported SAS/SATA backplane configurations. The
server supports 2.5-inch hot-swap SAS or hot-swap SATA hard disk drives, 2.5-inch hot-swap SATA
solid-state drives, or 1.8-inch hot-swap SATA solid-state drives. You can mix drives in the same server if
you do not mix drives on the same array.

Backplanes

IBM System x3750 M4 server supports various internal storage configurations based on four different
backplanes:

- 4-drive backplane for 2.5-inch drives: Up to four backplanes can be installed, each requiring one SAS connection to a supported controller. One RAID controller can connect to two of these backplanes.
- 8-drive backplane for 2.5-inch drives: Up to two backplanes can be installed, each requiring two SAS connections. One RAID controller per backplane.
- 8-drive backplane with a SAS expander for 2.5-inch drives: Use with the other 2.5-inch drive backplanes (8-drive or one 4-drive or two 4-drive backplanes) which will result in being able to
connect up to 16 2.5-inch drive bays to the one RAID controller.
- 8-drive backplane for 1.8-inch solid-state drives (eXFlash Pack): Up to four backplanes can be installed, each requiring two SAS connections. One RAID controller per backplane. Cannot be
connected to the 8-drive backplane with a SAS expander.

When building drive backplane configurations, all 1.8-inch SSD drive backplanes must be installed to the right of all 2.5-inch HDD or 2.5-inch SSD drive backplanes (when looking at the front of the server). Every four drives uses a SAS signal cable except when the 8-drive backplane with SAS expander is used. When the 8-drive backplane with SAS expander is used, the other backplanes connect to the SAS expander backplane with the supplied cables and then the SAS expander backplane is connected to the single RAID controller with two cables. All backplane options include the necessary cables.