Asus Comprehensive CPU Support List and Memory Limitations for P5B and P5B Deluxe

•If you install four 1 GB memory modules, the system may detect less than 3 GB of total memory because of address space allocation for other critical functions. This limitation applies to Windows XP 32-bit version operating system since it does not support PAE (Physical Address Extention) mode.

•If you install Windows XP 32-bit version operating system, we recommend that you install less than 3GB of total memory.

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.

32-bit

Windows 2000 Advanced Server

64-bit

Windows XP Professional x64 Edition

•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.

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