Asus M3N78-CM - Manual (Page 27)

ASUS M3N78-CM 1-15
• When using only one memory module, start installing the DDR2 DIMM from
slot DIMM_A1 or DIMM_B1 for better overclocking capability.
• Always use identical DDR2 DIMM pairs for dual channel mode. For
optimum compatibility, we recommend that you obtain memory modules
from the same vendor.
• If you are using a Windows 32-bit version operating system (e.g. 32-bit
Windows, 32-bit Vista), the system will allocate a certain amount of memory
space for system devices.
• When installing total memory of 4GB capacity or more, Windows ® 32-bit
operation system may only recognize less than 3GB. Hence, a total
installed memory of less than 3GB is recommended.
64-bit
Windows ® XP Professional x64 Edition
Windows ® Vista x64 Edition
The motherboard can support 8 GB physical memory on the operating system
listed below. You may install a maximum of 2 GB DIMMs on each slot.