What exactly is a memory bank? | Tom's Hardware Forum

A memory bank is a functionally independent memory device that is constructed in parallel with other banks in order to increase the ... Menu Menu Forums Login Register Sidebar Blog Categories Category1 Category2 Category3 Category4 Categories Category1 Category2 Category3 Category4 SupportUI.X Donate Contactus MainLinks Forums articles Interviews Menu Featured Home Forums Newposts Trending Searchforums What'snew Newposts Newprofileposts Latestactivity Members Currentvisitors Newprofileposts Searchprofileposts Billboard Trophies CatchtheTom'sHardwareShowonThursday,November4at3PMEastern! Whatexactlyisamemorybank? Threadstarter Loading000 Startdate Jan13,2017 Sidebar Forums Hardware Memory Previous Next Sortbyvotes L Loading000 Commendable Mar12,2016 22 0 1,510 0 Iamwonderingwhatisamemorybankandwhatexactlyitdoes?Doesiteffectraminanyway?   0 P Pinhedd Champion Moderator Aug7,2007 10,344 19 56,965 1,847 Loading000: Iamwonderingwhatisamemorybankandwhatexactlyitdoes?Doesiteffectraminanyway? Amemorybankisafunctionallyindependentmemorydevicethatisconstructedinparallelwithotherbanksinordertoincreasethethroughputofthememoryarchitecture. ManytypesofRAMandevensomenon-volatilestorageusemultiplememorybanks.ForthepurposesofkeepingthingsbriefandnotoverlytechnicalI'lldetailhowmemorybanksworkinDDR3andDDR4SDRAM. AllDDR3chipscontaineightfullyindependentmemorybankstiedtoasharedIOinterface.A4gigabitDDR3die(thelargestcapacityproduced)isactuallyconstructedfromeight512megabitmemorybanks.Duringoperation,eachrankhasonerowopenfromalloftherowsinitsownmemory;amemorybankcannotopenarowinanotherbank'smemory.Whenacommandissenttotheselectedrank,theBankAddressisusedtodeterminewhichmemorybankthecommandistobesentto.Thechip'sinternaldecodingcircuitrytakescareoftherest.SincetheIObusisshared,caremustbetakentoavoidsendingcommandstobankssuchthattheresultsmayoverlap. Considerthefollowing: ACPUcontainsasingledual-channelDDR3SDRAMcontroller. EachmemorychannelispopulatedbytwoDIMMs. EachDIMMcontainstworanks. Eachrankisconstructedfrom4gigabitDDR3SDRAMchips. Now,letsdosomemath. <2DIMMsperchannel>*<2ranksperDIMM>=4ranksperchannel <4ranksperchannel>*<8banksperrank>=32banksperchannel.Sinceeachbankhasitsownopenrow,morebanksisbetter! <8kilobitsperrow>*<65,536rowsperbank>=512megabitsperbank <512megabitsperbank>*<8banksperdie>=4gigabitsperdie <64IObitsperrank>/<8IObitsperdie(inthisexample)>=8chipsperrank <8chipsperrank>*<1dieperchip>*<4gigabitsperdie>=32gigabitsperrank <32gigabitsperrank>/<8bitsperbyte>=4gigabytesperrank <4gigabytesperrank>*<2ranksperDIMM>=8gigabytesperDIMM <8gigabytesperDIMM>*<2DIMMsperchannel>=16gigabytesperchannel <16gigabytesperchannel>*<2channels>=32gigabytesinstalled Sinceeachbankhasonerowoutof65,536open,thememorycontrollermustknowtheprecisestateofeachbankunderitscommand.Thegreaterthenumberofbanksinstalled,thegreaterthelikelihoodthatthememorycontrollerwillbeabletoreorderandscheduleacommandwithouthavingtoopenanewrowonabank,whichisatimeconsumingtask. DDR4worksslightlydifferently.WhereasDDR3haseightfullyindependentbanks,DDR4hasfourfullyindependentbankgroups,witheachbankgrouphavingfoursemi-independentbankswithinit.TheprincipleandmathematicsbehinditarethesamebutDDR4hasadditionaltimingconstraintsnotpresentinDDR3.   1 LilDog1291 Honorable Jan9,2013 313 0 10,960 56 Canyouprovideanexampleofwhatyoumean?Alinkorasourcethatyou'reseeing?   0 nzalog Respectable BANNED Jan2,2017 541 0 2,160 61 Prettysureitjustawaytogroupmemory. Youcouldsaydimm1and3arebank1anddimm2and4arebank2. Idon'tthinkit'sahighlytechnicaltermandcanbeusedindifferentwaysandevenpairedornotpairedatall.   0 Eximo Titan Ambassador May27,2010 20,033 1,382 90,040 4,476 Memorybankisaprettygenericterm,itcouldbereferringtotheRAMitself.   0 Flyfisherman Distinguished May29,2012 1,106 2 19,965 238 Hi, Ithinkthiswillexplainwhatamemorybankis:Techopedia:MemoryBank Yes,itwillinsomecircumstancesuseabitofYourRAM,dependingofwhatYou'retalkingabouthere. BestregardsfromSweden   0 Eximo Titan Ambassador May27,2010 20,033 1,382 90,040 4,476 nzalog: Prettysureitjustawaytogroupmemory. Youcouldsaydimm1and3arebank1anddimm2and4arebank2. Idon'tthinkit'sahighlytechnicaltermandcanbeusedindifferentwaysandevenpairedornotpairedatall. Normallythesearereferredtoaschannels.Ithinkthebankwouldapplytoalloftheslotstakenasawhole.Butwearegettingdownintosemanticsandnotanyrealdefinition.   0 nzalog Respectable BANNED Jan2,2017 541 0 2,160 61 Eximo: nzalog: Prettysureitjustawaytogroupmemory. Youcouldsaydimm1and3arebank1anddimm2and4arebank2. Idon'tthinkit'sahighlytechnicaltermandcanbeusedindifferentwaysandevenpairedornotpairedatall. Normallythesearereferredtoaschannels.Ithinkthebankwouldapplytoalloftheslotstakenasawhole.Butwearegettingdownintosemanticsandnotanyrealdefinition. Beingthat"memorybank"isnotreallyahighlytechnicalterm,anentirememorychannelorentiredimm,orallthememorycouldallbeconsideredamemorybanksinceevenadimmismadeupacollectionofmemorychips. Itmakesmoresenseformassiveserversthathave8orsoaddoncardsthathave10dimmseachonthem.You'dcallthefirstaddoncardbank1orsomethinglikethat.It'sjustdoesn'tmeananythingspecific. Ithinkthebestwaytosumitupisagroupingofmemory.   0 Eximo Titan Ambassador May27,2010 20,033 1,382 90,040 4,476 Notanexpansivewikipediaarticlewithonlyasinglereference,soIreallywouldn'tcallitdefinitive.I'mtoolazytolookupthesourcematerial. Butsimilartermsareusedinotherfields.Capacitorbank.Asinglecapacitormadeupofmanycapacitorsinparallel. Batterybank,typicallyabatteryusedtochargeotherbatteries.Thoughitalsoreferstoagroupingofbatteries(whichthemselvescouldbecalledcellbanksifyouwantedtogetfancy) Ithinkweusedtohavea286or386thattookanadd-incardfullof30-pinSIMMs.Probablyjustcalleditamemoryexpansioncardthough.Alsohadmotherboardsthattookextendedmemorymodulesbeforeonboardlevel2cachewasathing.   0 bloodroses Distinguished Jan27,2013 672 14 19,165 56 It'saplacetostoreyourRAMsoyougaininterestoffofit. Butseriously,itcanrefertomultiplethings.WhenIwastakingprogrammingclasses,itwasatermusedforthe'reserved'sectionofmemorythatwewereeitherallowedornotallowedtowriteto.Samewithclustersofmemorybasedonthesamehighestbitvalue. Onmotherboards,I'veheardthetermusedtoreferencethegroupslotsusedfordualandquadchannelmemory. WiththeoldSoundBlasteraudiocards,itwastheRAMusedtostoreMIDIsamples. Therearemanyotherexamples.   0 P Pinhedd Champion Moderator Aug7,2007 10,344 19 56,965 1,847 Loading000: Iamwonderingwhatisamemorybankandwhatexactlyitdoes?Doesiteffectraminanyway? Amemorybankisafunctionallyindependentmemorydevicethatisconstructedinparallelwithotherbanksinordertoincreasethethroughputofthememoryarchitecture. ManytypesofRAMandevensomenon-volatilestorageusemultiplememorybanks.ForthepurposesofkeepingthingsbriefandnotoverlytechnicalI'lldetailhowmemorybanksworkinDDR3andDDR4SDRAM. AllDDR3chipscontaineightfullyindependentmemorybankstiedtoasharedIOinterface.A4gigabitDDR3die(thelargestcapacityproduced)isactuallyconstructedfromeight512megabitmemorybanks.Duringoperation,eachrankhasonerowopenfromalloftherowsinitsownmemory;amemorybankcannotopenarowinanotherbank'smemory.Whenacommandissenttotheselectedrank,theBankAddressisusedtodeterminewhichmemorybankthecommandistobesentto.Thechip'sinternaldecodingcircuitrytakescareoftherest.SincetheIObusisshared,caremustbetakentoavoidsendingcommandstobankssuchthattheresultsmayoverlap. Considerthefollowing: ACPUcontainsasingledual-channelDDR3SDRAMcontroller. EachmemorychannelispopulatedbytwoDIMMs. EachDIMMcontainstworanks. Eachrankisconstructedfrom4gigabitDDR3SDRAMchips. Now,letsdosomemath. <2DIMMsperchannel>*<2ranksperDIMM>=4ranksperchannel <4ranksperchannel>*<8banksperrank>=32banksperchannel.Sinceeachbankhasitsownopenrow,morebanksisbetter! <8kilobitsperrow>*<65,536rowsperbank>=512megabitsperbank <512megabitsperbank>*<8banksperdie>=4gigabitsperdie <64IObitsperrank>/<8IObitsperdie(inthisexample)>=8chipsperrank <8chipsperrank>*<1dieperchip>*<4gigabitsperdie>=32gigabitsperrank <32gigabitsperrank>/<8bitsperbyte>=4gigabytesperrank <4gigabytesperrank>*<2ranksperDIMM>=8gigabytesperDIMM <8gigabytesperDIMM>*<2DIMMsperchannel>=16gigabytesperchannel <16gigabytesperchannel>*<2channels>=32gigabytesinstalled Sinceeachbankhasonerowoutof65,536open,thememorycontrollermustknowtheprecisestateofeachbankunderitscommand.Thegreaterthenumberofbanksinstalled,thegreaterthelikelihoodthatthememorycontrollerwillbeabletoreorderandscheduleacommandwithouthavingtoopenanewrowonabank,whichisatimeconsumingtask. DDR4worksslightlydifferently.WhereasDDR3haseightfullyindependentbanks,DDR4hasfourfullyindependentbankgroups,witheachbankgrouphavingfoursemi-independentbankswithinit.TheprincipleandmathematicsbehinditarethesamebutDDR4hasadditionaltimingconstraintsnotpresentinDDR3.   Youmustloginorregistertoreplyhere. Share: Facebook Twitter Reddit Tumblr WhatsApp Email Link Threadstarter Similarthreads Forum Replies Date QuestionSuggestionforMemory? Memory 10 Yesterdayat10:25PM T Question2or4sticksonaMSIMPGX570GAMINGEDGEWIFI Memory 1 Fridayat1:41PM S QuestionMemoryforRyzen5900X Memory 8 Fridayat12:18PM K QuestionMemorycache Memory 2 Fridayat8:31AM S [SOLVED]Whatfactorscontributetoamemoryleak? Memory 10 Wednesdayat10:03PM [SOLVED]AsusROGG752VSKMemoryUpgradeDDR43200onlyrunningat1600Mhz Memory 8 Tuesdayat2:34AM QuestionDoRyzen9CPUstakeadvantageofRAMspeedoutofthebox? Memory 5 Oct30,2021 G QuestionWhatssdisgoodforthismotherboard? Memory 9 Oct29,2021 C QuestionEXTREMELYHighMemoryUsage Memory 5 Oct27,2021 O QuestionG.skill3600mhzmemorynotworkingonryzen2700x+b450 Memory 6 Oct26,2021 Similarthreads Question SuggestionforMemory? Question 2or4sticksonaMSIMPGX570GAMINGEDGEWIFI Question MemoryforRyzen5900X Question Memorycache [SOLVED] Whatfactorscontributetoamemoryleak? [SOLVED] AsusROGG752VSKMemoryUpgradeDDR43200onlyrunningat1600Mhz Question DoRyzen9CPUstakeadvantageofRAMspeedoutofthebox? Question Whatssdisgoodforthismotherboard? Question EXTREMELYHighMemoryUsage Question G.skill3600mhzmemorynotworkingonryzen2700x+b450 ASKTHECOMMUNITY Forum Hardware   GraphicsCards   Systems   Components   CPUs   Motherboards   Storage   Overclocking   Memory   Displays     VR&AR   Prebuilt&Enterprise   Cases   Cooling   PowerSupplies   RaspberryPi&SingleBoardComputers Software   Windows11   Windows10   WindowsLegacy   Windows7   WindowsVista   WindowsXP   macOS   OpenSource   PCGaming   Antivirus/Security/Privacy   AppsandSoftware Networking   Networking   WirelessNetworking   WirelessCarriers   DistributedComputing LaptopsandMobileDevices   Android&ChromeOS   LaptopGeneralDiscussion   LaptopTechSupport   Macbooks Electronics   ComputerPeripherals   DigitalCameras   HomeAudio&Theater   ConsumerElectronics Community   ForumRules&Feedback   ReviewComments   NewsComments BeyondtheKeyboard   Hobbies&Leisure   Entertainment   Cars   Work&Education Legacy   Classifieds   OpinionsandExperiences   PhotoReportComments Title Message Postthread TRENDINGTHREADS News IntelCorei9-12900KandCorei5-12600KReview:RetakingtheGamingCrown StartedbyAdmin Thursdayat9:10AM Replies:134 NewsComments P Question 2070Supergivingmeworseframesthana1060? StartedbyPaul-Smenis Oct7,2021 Replies:30 GraphicsCards Question Pccrashingonwarzoneblackscreenwithredsquares StartedbyJuan2508 Todayat12:58AM Replies:9 GraphicsCards Question i7-10700reaching100ºC(212ºF),CPUCoolerissue? Startedbyxxxbabyxxx Todayat12:08AM Replies:18 CPUs Question IstheSamsung970evopluscompatiblewithGigabyteB560HD3motherboard? Startedbyangeln23 Yesterdayat2:26PM Replies:22 Storage Question NeedhelpinstallingmyEVGA650WBQ? StartedbyPerflext Yesterdayat8:50PM Replies:24 PowerSupplies J Info ReviewmyBuild StartedbyJetFury Todayat1:44AM Replies:3 Components Latestposts S Question Is650Wenoughformodernpc? Latest:--SID-- 2minutesago PowerSupplies S Question PSUprobablydead;shouldIrisktestingmypartswithit? Latest:--SID-- 5minutesago PowerSupplies T Question UpgradeMemoryonTomahawkM270(MS-7A68) Latest:Torque22 6minutesago Motherboards S Question Nosignalonmonitor Latest:--SID-- 7minutesago Displays S Question CorsairVengeanceLPXDDR4-3200andGigabyteZ690GamingXDDR4issue Latest:--SID-- 9minutesago Memory V Question DolbyAccess Latest:Vulse 11minutesago Windows10 L Question Overclockingnewbie-helpisneeded! Latest:Lycanious 18minutesago Overclocking Moderatorsonline Sharethispage Facebook Twitter Reddit Tumblr WhatsApp Email Link Forums Hardware Memory COMPANY Tom'sHardwareispartofFutureplc,aninternationalmediagroupandleadingdigitalpublisher.Visitourcorporatesite. ©FuturePublishingLimitedQuayHouse,TheAmbury,BathBA11UA.Allrightsreserved.EnglandandWalescompanyregistrationnumber2008885. RESOURCES Advertising CookiesPolicies Privacy Term&Conditions Topics FOLLOW Facebook Twitter