Lenovo System x3250 M5 - Page 183

•U=UnbufferedDIMMwithnoECC(x64-bitprimarydatabus)
–aaistheCASlatency,inclocksatmaximumoperatingfrequency
–bbistheJEDECSPDRevisionEncodingandAdditionslevel
–ccisthereferencedesignfileforthedesignoftheDIMM
Notes:
1.TodeterminethetypeofaDIMM,seethelabelontheDIMM.Theinformationonthelabelisinthe
formatxGBnRxxPC3v-xxxxxx-xx-xx-xx.Thenumeralinthesixthnumericalpositionindicates
whethertheDIMMissingle-rank(n=1)ordual-rank(n=2).
2.Theamountofusablememoryisreduced,dependingonthesystemconfiguration.Acertain
amountofmemorymustbereservedforsystemresources.Toviewthetotalamountofinstalled
memoryandtheamountofconfiguredmemory,runtheSetuputility.Foradditionalinformation,see
“Configuringtheserver”onpage86
.
ThefollowingillustrationshowsthelocationoftheDIMMconnectorsonthesystemboard.
Figure96.ThelocationoftheDIMMconnectorsonthesystemboard
ThefollowingsectionsprovideadditionalinformationspecifictounbufferedandregisteredDIMMsthat
youmustconsider.
UnbufferedDIMMs(UDIMMs)
ThefollowingnotesprovideinformationthatyoumustconsiderwhenyouinstallUDIMMs.
•ThememorychannelsrunatthelowestcommonfrequencyoftheDIMMsinstalled.
•TheUDIMMoptionsthatareavailablefortheserverare1GB,2GB,4GB,and8GB(whenavailable)
DIMMs.
•Theserversupportsuptotwosingle-rankordual-rankUDIMMsperchannel.
•ThefollowingtableliststhesupportedUDIMMpopulation.
Chapter6.Removingandreplacingservercomponents169