Asus P5QL-EM - Manual (Page 28)

1-16 Chapter 1: Product introduction
1.7.2 Memory configurations
You may install 256 MB, 512 MB, 1 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.
• Due to chipset limitation, this motherboard only supports up to the total of four
ranks (four sides in total) of RAM at max.
• When installing total memory of 4GB capacity or more, Windows 32-bit operation
system may only recognize less than 3GB. Hence, a total installed memory of
less than 3GB is recommended.
• If you install Windows ® XP/Vista 32-bit operation system, a total memory of
less than 3GB is recommended.
• This motherboard does not support memory modules made up of 128 Mb
chips.
• When using only one memory module, start installing the DDR2 DIMM from
slot DIMM_A1 or DIMM_B1 for better overclocking capability.
• For dual-channel configuration, you may:
- install identical DIMMs in all four sockets OR
- install identical DIMM pair in DIMM_A1 and DIMM_B1 (yellow sockets)
and another identical DIMM pair in DIMM_A2 and DIMM_B2 (black
sockets)
• Always use identical DDR2 DIMM pairs for dual channel mode. For
optimum compatibility, we recommend that you obtain memory modules
from the same vendor.