Dimm Sockets - HP xw3100 Service And Technical Reference Manual

Memory

DIMM Sockets

There are four DIMM sockets on the system board, with two sockets per channel. The sockets are
labeled XMM1, XMM2, XMM3, and XMM4. Sockets XMM1 and XMM2 operate in memory
channel A. Sockets XMM3 and XMM4 operate in memory channel B.
Item
DIMM socket XMM1, Channel A
1
DIMM socket XMM2, Channel A
2
DIMM socket XMM3, Channel B
3
DIMM socket XMM4, Channel B
4
The system will automatically operate in single channel mode or a higher-performing dual
channel mode, depending on how the DIMMs are installed.
In single channel mode, the maximum operational speed is determined by the slowest DIMM
in the system. For example, if the system is populated with a DIMM that is 333 MHz and a
second DIMM that is 400 MHz, the system will run at the slower of the two speeds.
In dual channel mode, the DIMM pairs must be identically matched. DIMMs in the XMM1
and XMM3 black sockets must be identical; DIMMs in the XMM2 and XMM4 blue sockets
must also be identical. Therefore, if you have one preinstalled DIMM in socket XMM1 and
are adding a second DIMM, it is recommended that you install an identical DIMM into the
XMM3 socket.
In dual channel mode, the DIMM pairs must be identically matched. DIMMs in the XMM1
and XMM3 black sockets must be identical; DIMMs in the XMM2 and XMM4 blue sockets
must also be identical. Therefore, if you have one preinstalled DIMM in socket XMM1 and
are adding a second DIMM, it is recommended that you install an identical DIMM into the
XMM3 socket. If you are populating all four DIMM sockets, use identical DIMMS in each
socket. Otherwise, the system will not operate in dual channel mode.
F–2
Description Socket Color
Black
Blue
Black
Blue
Service and Technical Reference Guide, xw3100