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.

✎The system board shown below may be slightly different from the one in the computer.

Item

Description

Socket Color

 

 

 

1

DIMM socket XMM1, Channel A

Black

 

 

 

2

DIMM socket XMM2, Channel A

Blue

 

 

 

3

DIMM socket XMM3, Channel B

Black

 

 

 

4

DIMM socket XMM4, Channel B

Blue

 

 

 

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 266 MHz and a second DIMM that is 333 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.

 

E–2

359782-002

Service Reference Guide, dx2000 uT