Asus P5E-VM DO - Manual (Page 32)

1-20 Chapter 1: Product introduction
• 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 1 GB memory modules, the system may detect less than
3GB because the address allocation for other critical functions. This limitation
applies to Windows ® Vista 32-bit/ Windows ® XP 32-bit version operation
system since it does not support Physical Address Extension (PAE) mode.
• This motherboard does not support memory modules made up of 128 Mb
chips or double sided x16 memory modules.
Notes on memory limitations
• Due to chipset limitation, this motherboard can only support up to
8 GB on the operating systems listed below. You may install a maximum of
2 GB DIMMs on each slot, but only DDR2-533 and DDR2-667 2 GB density
modules are available for this configuration.
• Some old-version DDR2-800 DIMMs may not match Intel ®
On-Die-Termination (ODT) requirement and will automatically downgrade
to run at DDR2-667. If this happens, contact your memory vendor to check
the ODT value.
• Due to chipset limitation, DDR2-800 with CL=4 will be downgraded to run
at DDR2-667 by default setting. If you want to operate with lower latency,
adjust the memory timing manually.
• The total memory may has 8MB reduction under Single Channel mode, and
16MB reduction under Dual Channel mode because the address space
is reserved for the Intel ® vPro ™ Technology and the Intel ® Quiet System
Technology.
64-bit
Windows XP Professional x64 Edition
Windows Vista Professional x64 Edition
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.