Asus P5B - Manual (Page 37)

ASUS P5B 2-
2.4 System memory
2.4.1 Overview
The motherboard comes with four Double Data Rate 2 (DDR2) Dual Inline Memory
Modules (DIMM) sockets.
A DDR2 module has the same physical dimensions as a DDR DIMM but has a
20-pin footprint compared to the 8-pin DDR DIMM. DDR2 DIMMs are notched
differently to prevent installation on a DDR DIMM socket.
The figure illustrates the location of the DDR2 DIMM sockets:
2.4.2 Memory configurations
You may install 256 MB, 52 MB, GB, and 2 GB unbuffered non-ECC DDR2
DIMMs into the DIMM sockets.
• You may install varying memory sizes in Channel A and Channel B. The
system maps the total size of the lower-sized channel for the dual-channel
configuration. Any excess memory from the higher‑sized channel is then
mapped for single-channel operation.
• Always install DIMMs with the same CAS latency. For optimum compatibility,
it is recommended that you obtain memory modules from the same vendor.
• If you install four or 2GB memory modules, the system may only recognize
less than GB because the address space is reserved for other critical
functions. This limitation appears on Windows ® XP 2-bit operation system
which does not support Physical Address Extension (PAE).
• If you install Windows ® XP 2-bit operation system, a total memory of less
than GB is recommended.
• This motherboard does not support memory modules made up of 28 Mb
chips or double sided x6 memory modules.
Channel Sockets
Channel A DIMM_A and DIMM_A2
Channel B DIMM_B and DIMM_B2
R
P5B
P5B 240-pin DDR2 DIMM Sockets
2 Pins
28 Pins
DIMM_A1 DIMM_A2 DIMM_B1 DIMM_B2