Hardware options installation 31
DIMM identification
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
Voltage rating
L = Low voltage (1.35v)
U = Ultra low voltage (1.25v)
Blank or omitted = Standard
5
Memory speed
12800 = 1600-MT/s
10600 = 1333-MT/s
8500 = 1066-MT/s
6
DIMM type
R = RDIMM (registered)
E = UDIMM (unbuffered with ECC)
L = LRDIMM (load reduced)
For the latest supported memory information, see the QuickSpecs on the HP website
(
http://h18000.www1.hp.com/products/quickspecs/ProductBulletin.html
). At the website, choose the
geographic region, and then locate the product by name or product category.
Memory configurations
To optimize server blade availability, the server blade supports the following AMP modes:
•
Advanced ECC—provides up to 4-bit error correction and enhanced performance over Lockstep mode.
This mode is the default option for this server blade.
•
Online spare memory—provides protection against failing or degraded DIMMs. Certain memory is
reserved as spare, and automatic failover to spare memory occurs when the system detects a DIMM that
