User manual

ASUS STRIX X99 GAMING
1-7
Chapter 1
Memory configurations
Youmayinstall2GB,4GBand8GBunbufferedandnon-ECCDDR4DIMMsintotheDIMM
sockets.
• YoumayinstallvaryingmemorysizesinChannelA,ChannelB,ChannelC,and
ChannelD.Thesystemmapsthetotalsizeofthelower-sizedchannelforthequad-
channelconguration.Anyexcessmemoryfromthehigher-sizedchannelisthen
mapped for single-channel operation.
• AccordingtoIntel
®
CPUspec,DIMMvoltagebelow1.65Visrecommendedtoprotect
theCPU.
• 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:
a) Useamaximumof3GBsystemmemoryifyouareusinga32-bitWindows
®
OS.
b) Installa64-bitWindows
®
OSwhenyouwanttoinstall4GBormoreonthe
motherboard.
c) Formoredetails,refertotheMicrosoft
®
support site at http://support.microsoft.
com/kb/929605/en-us.
• 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3.5 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(8DIMMs)oroverclockingcondition.
• AlwaysinstalltheDIMMSwiththesameCASLatency.Foranoptimumcompatibility,
werecommendthatyouinstallmemorymodulesofthesameversionordatacode
(D/C)fromthesamevendor.Checkwiththevendortogetthecorrectmemory
modules.
• ThedesignoftheDIMMfanmayvary.EnsurethattheDIMMfantstothe
motherboard.