Asus M3A78-CM - Manual (Page 22)

1.7.2 Memory configurations
You may install 256MB, 512MB, 1GB and 2GB unbuffered ECC/non-ECC DDR2 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.
• 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 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 when you want to install 4GB or more memory on
the motherboard.
• This motherboard does not support DIMMs made up of 256 megabits (Mb) or less.
The motherboard supports up to 8GB memory modules on Windows ® XP Professional x64
and Vista x64 editions. You may install a maximum of 2 GB DIMMs on each slot.
M3A78-CM Motherboard Qualified Vendors Lists (QVL)
DDR2-1066MHz capability
• Due to AM2+ CPU limitation, only one DDR2 1066 DIMM is supported per channel.
When two DDR2 1066 DIMMs are installed, all DIMMs run at 800Mhz frequency by
default for system stability.
• The default DIMM frequency depends 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.
Size Vendor Part No. CL Chip Brand SS/
DS
Chip No.
DIMM support
A* B* C*
512MB Kingston KVR1066D2N7/512 N/A Elpida SS E5108AJBG-1J-E • •
1G Kingston KHX8500D2/1G N/A Kingston DS Heat-Sink Package • •
1G Qimonda HYS64T128020EU-19F-C 6 Qimonda DS HYB18T512800CF19FFSS24313 • •
1G Kingmax KLED48F-A8K15 N/A Kingmax DS KKA8FFIXF-JFS-18A • •
1G Transcend TX1066QLJ-2GK1GB 5 Transced DS Heat-Sink Package • •
1G OCZ OCZ2N1066SR2DK N/A OCZ DS Heat-Sink Package • •
1G GEIL GE22GB1066C5DC 5 GEIL DS Heat-Sink Package • •
1G GEIL GE24GB1066C5QC 5 GEIL DS Heat-Sink Package • •
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