Asus M2N68 AM User Manual - Page 21

1.7.2 Memory configurations You may install 256MB, 512MB, 1GB, and 2GB 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 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, we recommend that you obtain memory modules from the same vendor. • Due to the memory address limitation on 32-bit Windows® OS, when you install 4GB or more memory on the motherboard, the actual usable memory for the OS can be about 3GB or less. For effective use of memory, we recommend that you do any of the following: - Use a maximum of 3GB system memory if you are using a 32-bit Windows® OS. - Install a 64-bit Windows® OS when you want to install 4GB or more memory on the motherboard. • This motherboard does not support DIMMs made up of 256 megabits (Mb) or less. The motherboard supports up to 4GB memory modules on Windows® XP Professional x64 and Vista x64 editions. You may install a maximum of 2GB DIMMs on each slot. M2N68-AM Motherboard Qualified Vendors Lists (QVL) DDR2-1066MHz capability Size 1G 1G 1G 512MB 1G Vendor Kingston Corsair Corsair ADATA ADATA Model CL KHX8500D2K2/2GN N/A CM2X1024-8500C5 N/A CM2X1024-8500C5D 5 M2OMIDG3H3160INC5Z 5 M2OMIDG314720INC5Z 5 Brand Kingston Corsair Corsair ADATA ADATA SS/DS Component SS Heat-Sink Package DS Heat-Sink Package DS Heat-Sink Package SS Heat-Sink Package DS Heat-Sink Package DIMM support A* B* • • • • • • • • • • • Due to AM2+ CPU limitation, only one DDR2 1066 DIMM is supported per channel. When two DDR2 1066 DIMMs are installed, all DIMMs run at 800Mhz frequency by default for system stability. • The default DIMM frequency depends on its Serial Presence Detect (SPD), which is the standard way of accessing information from a memory module. Under the default state, some memory modules for overclocking may operate at a lower frequency than the vendor-marked value. Chapter 1: Product introduction 1-11