Memory Configurations - Asus SABERTOOTH 990FX GEN3 R2.0 User Manual

Memory configurations

You may install 1GB, 2GB, 4GB, 8GB, and 16GB ECC, non-ECC and unbuffered DDR3
DIMMs into the DIMM sockets.
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Memory module with memory frequency higher than 2133 MHz and its corresponding
timing or the loaded DRAM OC Profile is not the JEDEC memory standard. The
stability and compatibility of these memory modules depend on the CPU's capabilities
and other installed devices.
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 CPU behavior, DDR3 1800 MHz memory module will run at the default
frequency of DDR3 1600 MHz.
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:
a) Use a maximum of 3GB system memory if you are using a 32-bit Windows OS.
b) Install a 64-bit Windows OS when you want to install 4GB or more on the
motherboard.
c) For more details, refer to the Microsoft
com/kb/929605/en-us.
This motherboard does not support DIMMs made up of 512Mb (64MB) chips or less
(Memory chip capacity counts in Megabit, 8 Megabit/Mb = 1 Megabyte/MB).
The default memory operation frequency is dependent 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. To operate at the vendor-marked
or at a higher frequency, refer to section 3.4 Ai Tweaker menu for manual memory
frequency adjustment.
For system stability, use a more efficient memory cooling system to support a full
memory load (4 DIMMs) or overclocking condition.
support site at http://support.microsoft.
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Chapter 1: Product introduction