Owner's Manual

ASUS B85M-G
1-7
1.4 System memory
1.4.1 Overview
This motherboard comes with four Double Data Rate 3 (DDR3) Dual Inline Memory Module
(DIMM) sockets. A DDR3 module has the same physical dimensions as a DDR2 DIMM but
is notched differently to prevent installation on a DDR2 DIMM socket. DDR3 modules are
developed for better performance with less power consumption. The gure illustrates the
location of the DDR3 DIMM sockets:
Channel Sockets
Channel A DIMM_A1 & DIMM_A2
Channel B DIMM_B1 & DIMM_B2
B85M-G
DIMM_A1 DIMM_A2 DIMM_B1 DIMM_B2
B85M-G 240-pin DDR3 DIMM sockets
1.4.2 Memory congurations
You may install 1GB, 2GB, 4GB, and 8GB unbuffered non-ECC DDR3 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.
• Due to Intel
®
chipset limitation, DDR3 1600MHz and higher memory modules on XMP
mode will run at the maximum transfer rate of DDR3 1600MHz.
• Always install DIMMs with the same CAS latency. For optimal compatibility, we
recommend that you install memory modules of the same version or date code (D/C)
from the same vendor. Check with the retailer to get the correct memory modules.
• 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 if you want to install 4GB or more on the
motherboard.
• This motherboard does not support DIMMs made up of 512 megabits (Mb) chips or
less.
• The maximum 32GB memory capacity can be supported with 8GB or above DIMMs.
ASUS will update the memory QVL once the DIMMs are available in the market.