Asus H81M-D R2.0 - Memory Configuration Guidelines

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Chapter 1: Product introduction
• 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conguration.Anyexcess
memoryfromthehigher-sizedchannelisthenmappedforsingle-channeloperation.
• DuetoIntel
®
chipsetlimitations,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512megabits(Mb)chipsor
less.
• Memorymoduleswithmemoryfrequencyhigherthan2133MHzanditscorresponding
timingortheloadedX.M.P.ProleisnottheJEDECmemorystandard.Thestability
andcompatibilityofthesememorymodulesdependontheCPU’scapabilitiesand
otherinstalleddevices.
• Themaximum16GBmemorycapacitycanbesupportedwith8GBoraboveDIMMs.
ASUSwillupdatethememoryQVLoncetheDIMMsareavailableinthemarket.
• 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.
• Forsystemstability,useamoreefcientmemorycoolingsystemtosupportafull
memoryload(2DIMMs)oroverclockingcondition.
• Refertowww.asus.comforthelatestMemoryQVL(QualiedVendorsList)
1.4.3 Installing a DIMM
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