The IBM BladeCenter AMD Opteron LS41 Multiprocessor Expansion Unit is an optional expansion unit for single-wide models of the BladeCenter LS41 Type 7972 blade server.
The Multiprocessor Expansion Unit provides up to eight additional dual-inline memory (DIMM) connectors, two additional microprocessors, and one SAS hard disk drive for use by the blade server. The expansion unit also supports installation of standard-form-factor, small-form-factor, or high-speed I/O-expansion cards. An additional expansion unit, such as the BladeCenter Storage Expansion Unit 3, can also be installed.
See the Installation Guide for the IBM BladeCenter AMD Opteron LS41 Multiprocessor Expansion Unit.
Go to http://www.ibm.com/systems/bladecenter/hardware/expansion/ for more information about expansion units.