Hardware options installation 31
The memory subsystem may be populated with either RDIMMs or UDIMMs, but mixing the two types is not
supported. To determine DIMM characteristics, use the label attached to the DIMM and the following
illustration and table.
Item Description
Definition
1 Size
—
2
Rank
1R = Single-rank
2R = Dual-rank
4R = Quad-rank
3
Data width
x4 = 4-bit
x8 = 8-bit
4
Memory speed
10600 = 1333-MHz
8500 = 1067-MHz
5
DIMM type
R = RDIMM (registered)
E = UDIMM (unbuffered with ECC)
For the latest supported memory information, see the QuickSpecs on the HP website
(
http://www.hp.com
).
Memory configurations
To optimize server blade availability, the server blade supports the following AMP modes:
•
Advanced ECC—provides the greatest memory capacity for a given DIMM size, while providing up
to 8-bit error correction, depending on the specific DIMM type. This mode is the default option for
this server blade.
•
Mirrored Memory—provides maximum protection against failed DIMMs. Uncorrectable errors in one
channel are corrected by the mirror channel.
•
Lockstep—provides enhanced protection while making all installed memory available to the
operating system. The server blade can continue to function if a single- or mulit-bit memory failure
within a single DRAM device occurs.