Asus Rampage II Extreme - Manual (Page 44)

2.4.2 Memory configurations
You may install 1GB and 2GB unbuffered non-ECC DDR3 DIMMs into the DIMM
sockets.
• The default memory operation frequency is dependent on its SPD. 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, see section 3.1 Extreme Tweaker menu for manual
memory frequency adjustment.
• For system stability, use a more efficient memory cooling system to support
a full memory load (6 DIMMs) or overclocking condition.
• You may install varying memory sizes in Channel A, Channel B and
Channel C. The system maps the total size of the lower-sized channel for
the dual-channel or triple-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 install a 64-bit Windows OS when having 4GB or
more memory installed on the motherboard.
• This motherboard does not support memory modules made up of 128 Mb
chips.
2-16 Chapter 2: Hardware information