Asus M4A78 - Manual (Page 22)

1.7.2 Memory configurations
You may install 512MB, 1GB, 2GB, and 4GB unbuffered 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 16GB memory modules on Windows ® XP Professional x64
and Vista x64 editions. You may install a maximum of 4GB DIMMs on each slot.
M4A78 Motherboard Qualified Vendors Lists (QVL)
DDR2-533MHz capability
Size Vendor Part No.
SS/
DS
CL Chip No.
Chip
Brand
DIMM support
A* B* C*
512MB Kingston KVR533D2N4/512 SS N/A HYB18T512808AF3S Qimonda · · ·
1G Kingston KVR533D2N4/1G DS N/A HY5PS12821EFP-Y5 Hynix · · ·
1G HY HYMP512U64CP8-C4 AB DS 4 HY5PS12821CFP-C4 Hynix · · ·
512MB Elpida EBE51UD8ABFA-5C-E SS N/A E5108AB-5C-E Elpida · · ·
512MB Transcend 512MB DDR2 533 ECC SS N/A 6ND22D9GCT(ECC) Micron · · ·
512MB Kingmax KLBC28F-A8KB4 SS N/A KKEA88B4IAK-37 Kingmax · · ·
1G Elixir M2Y1G64TU8HBOB-37B DS 4 N2TU51280BE-37B61921300CP Elixir · · ·
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