IBM H SERIES RS/6000 - Manual (Page 20)

The maximum configuration of the RS/6000 Enterprise Server Model H Series can
include:
Four PowerPC processors
8GB system memory
Twelve 9.1GB internal hot-swappable disk drives
One 1.44MB diskette drive
One CD-ROM drive
One additional media device (may be a tape drive, CD-ROM drive, or a
non-hot-swappable disk drive).
Two power supplies (which provide redundant power).
Two backplanes that can accept up to twelve hot-swappable disk drives (may be
either SCSI or SSA)
1-2 RS/6000 Enterprise Server Model H Series User's Guide