Asus P5K WS Computer Hardware User Manual


 
2-14 Chapter 2: Hardware information
32-bit 64-bit
Windows
®
2000 Advanced Server Windows
®
XP Professional x64 Edition
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 conguration.
Some old-version DDR2-800/667 DIMMs may not match Intel
®
’s
On-Die-Termination (ODT) requirement and will automatically downgrade
to run at DDR2-533. 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.
Due to chipset limitation, DDR2-667 with CL=3 will be downgraded to run
at DDR2-533 by default setting. If you want to operate with lower latency,
adjust the memory timing manually.
2.4.2 Memory congurations
You may install 256 MB, 512 MB, 1 GB, and 2 GB unbuffered ECC / 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
conguration. 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 2GB memory modules, the system may only recognize less
than 8GB because the address space is reserved for other critical functions.
This limitation appears on Windows
®
XP 32-bit operation system which does
not support Physical Address Extension (PAE).
If you install Windows
®
XP 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 or double sided x16 memory modules.