Specifications

ASUS A68HM Series
1-7
1.4.2 Memory configurations
Youmayinstall1GB,2GB,4GB,and8GBunbufferednon-ECCDDR3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conguration.Anyexcess
memoryfromthehigher-sizedchannelisthenmappedforsingle-channeloperation.
• 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:
 - Installamaximumof3GBsystemmemoryifyouareusinga32-bitWindows®
 OS.
- Usea64-bitWindows
®
OSifyouwanttoinstall4GBormorememoryonthe
motherboard.
• ThismotherboarddoesnotsupportDIMMsmadeupof512Mb(64MB)chipsorless.
• Themaximum32GBmemorycapacitycanbesupportedwith16GB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.Tooperateatthevendor-marked
oratahigherfrequency,refertosection2.5 Ai Tweaker menu for manual memory
frequencyadjustment.
• 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).
E9808_A68HM Series_Manual.indb 7 2014/10/16 10:09:02