User's Manual

1-8

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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3GB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.

 - 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2.5 Ai Tweaker menu for manual memory

frequencyadjustment.

• 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.

• VisittheASUSwebsiteatwww.asus.comforthelatestQVL.

1.4.3 Installing a DIMM