Lenovo System x3550 M5 - Memory Rank Sparing

Memoryranksparing
Thememoryranksparingfeaturedisablesthefailedmemoryfromthesystemconfigurationandactivatesa
ranksparingDIMMtoreplacethefailedactiveDIMM.
YoucanenableranksparingmemoryintheSetupUtility,selectSystemSettings➙Memory.Formore
information,see“UsingtheSetupUtility”onpage36.
Themaximumavailablememoryisreducedwhenmemoryranksparingmodeisenabled.
ThememoryranksparingmoderequiresanevennumberofDIMMs.Ifyourserverhasanoddnumberof
DIMMsinstalled,ensurethatyoudisablethememoryranksparingmodefromtheMemorymenuinSetup
Utility.See“UsingtheSetupUtility”onpage36.
Note:Afterdisablingthememoryranksparingmode,ifamessagepromptsthatthememoryconfigurationis
notvalid,restarttheIMM2.Alternatively,youcanturnofftheserver,disconnectitfromandthenreconnect
ittoacpower,andthenturnontheserveragain.
ThefollowingdiagramliststheDIMMconnectorsoneachmemorychannel.
Figure88.Connectorsoneachmemorychannel
Followtheinstallationsequenceforranksparingmode:
•Installatleastonequad-rankDIMMinachannel.
•Installatleasttwosingle-rankordual-rankDIMMsinachannel.
Table29.MemoryranksparingmodeDIMMpopulationsequencewhenonlyquad-rankRDIMMsareinstalled
Numberofinstalled
microprocessorsDIMMconnectorpopulationsequenceonthesystemboard
One
1,4,9,12,2,5,8,11
Two1,13,4,16,9,21,12,24,2,14,5,17,8,20,11,23
Table30.MemoryranksparingmodeDIMMpopulationsequencewhensingle/dual/quadrankDIMMsareinstalledand
thetotalnumberofDIMMsiseven
DIMMs
Numberofinstalled
microprocessors
DIMMconnectorpopulation
sequenceonthesystemboard
OneMicroprocessor
1stset11,2
2ndset14,5
3rdset18,9
4thset111,12
Chapter5.Removingandreplacingcomponents165