Hardware options installation 29
This setting preserves maximum memory subsystem performance. To have DIMMs operate at 1.35V,
configure the Maximum Memory Bus Frequency option in the ROM-Based Setup Utility to 1066 MHz.
• If there is one quad-rank LVDIMM per channel on any populated memory channel in the system running
at 1066 MHz, the LVDIMMs operate at 1.5V.
This setting preserves maximum memory subsystem performance. To have DIMMs operate at 1.35V,
configure the Maximum Memory Bus Frequency option in the ROM-Based Setup Utility to 800 MHz.
LVDIMMs are only supported for use with the Intel® Xeon® 5600 series of processors.
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)
Blank or omitted = Standard
5
Memory speed 10600 = 1333-MHz
8500 = 1066-MHz
6
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).
