HP ProLiant DL385 G7 Server - Manual (Page 49)

Hardware options installation 49
• Advanced ECC is not available if x4 and x8 memory modules are mixed in channels (A and B), (C
and D), or both, but standard ECC is still available. Advanced ECC is available if x4 and x8
memory modules are mixed in memory channels (A and C), (B and D), or both.
• No more than two UDIMMs may be installed per channel.
• Do not mix UDIMMs and RDIMMs within this server.
Population guidelines
While adhering to the memory population rules (" Population rules " on page 48 ), performance can be
improved by following the guidelines below:
• Memory modules may be installed one at a time per processor, but installing two at a time per
processor provides for additional performance, installing four at a time per processor provides for
better performance, and installing equal amounts of memory for both processors provides for best
performance.
• Install all memory modules of the same speed on the same processor for best performance.
• Install all memory modules of the same voltage on the same processor for best power.
Memory bus speed
Depending on the quantity and native speed of memory modules installed, memory bus speeds can be
1333 MHz, 1066 MHz, 800 MHz, or 667 MHz. Memory bus speeds can be different for each
processor.
To determine memory bus speeds, do the following:
1. Within RBSU, select the Power Management Options menu > Advanced Power Management Options
menu > Maximum Memory Bus Frequency menu.
2. Select one of the following menu options:
o Auto (default)—The memory bus speed is set to what is shown in the following table. If the native
speed of the installed memory module is slower than the memory bus speed, the memory bus
speed is set to the memory module native speed
Memory
modules per
channel
QR SR or DR Memory
module native
speed
Memory bus speed
(standard-voltage
memory module)
Memory bus speed
(low-voltage memory
module)
1 — 1* SR 1333 MHz
DR 1333 MHz
DR 1066 MHz 1333 MHz 1333 MHz
1 1 — QR 1066 MHz 1066 MHz 1066 MHz
2 — 2* SR 1333 MHz
DR 1333 MHz
DR 1066 MHz 1333 MHz 1333 MHz
2 1 1 SR 1333 MHz
DR 1333 MHz
DR 1066 MHz
QR 1066 MHz 800 MHz 800 MHz
3 — 3 SR SR 1333 MHz 1333 MHz 1066 MHz