1.4System memory

1.4.1Overview

This motherboard comes with four Double Data Rate 3 (DDR3) Dual Inline Memory Module (DIMM) sockets. A DDR3 module is notched differently from a DDR or DDR2 module. DO NOT install a DDR or DDR2 memory module to the DDR3 slot.

According to Intel® CPU spec, DIMM voltage below 1.65V is recommended to protect the CPU.

DIMM A1 DIMM A2

DIMM B1 DIMM B2

B85-PLUS

Channel Sockets

Channel A DIMM_A1 & DIMM_A2 Channel B DIMM_B1 & DIMM_B2

B85-PLUS 240-pin DDR3 DIMM sockets

1.4.2Memory configurations

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 configuration. 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 512Mb (64MB) chips or less.

ASUS B85-PLUS

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