Asus P3-P5G31 User Manual - Page 27

2.5.1 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. • 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 are using a Windows 31-bit version operating system (e.g. 32-bit Windows XP, 32-bit Windows Vista) without the Physical Address Extension (PAE) support, the system will allocate a certain amount of memory space for system devices. • We recommend that you install only a maximum of 3GB system memory when using a Windows 32-bit version operating system without the PAE. The excess over 3GB of installed memory will not cause any problem; however, the system can not use this excess memory space and the system will display less than the total size of physical memory installed. • 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 4 GB on the operating systems listed below. You may install a maximum of 2 GB DIMMs on each slot, but only DDR2-800 and DDR2-667 2 GB density modules are available for this configuration. 32-bit Windows® XP Windows® 2003 Server Windows® Vista 64-bit Windows® XP x64 Edition Windows® 2003 Server x64 Edition Windows® Vista x64 Edition • Some old-version DDR2-800 DIMMs may not match Intel® On-Die-Termination (ODT) requirement and will automatically downgrade to run at DDR-667. If this happens, contact your memory vendor to check the ODT value. ASUS P3-P5G31 2-11