Ze li txhua lub khoos phis tawj muaj peev xwm xav tau RAM. Ua tib zoo saib ntawm koj lub cuab yeej nyiam (xws li smartphones, ntsiav tshuaj, desktops, laptops, graphing calculators, HDTVs, handheld gaming systems, etc.), thiab koj yuav tsum nrhiav qee cov ntaub ntawv hais txog RAM. Txawm hais tias tag nrho RAM pib ua haujlwm tib lub hom phiaj, muaj ob peb hom sib txawv uas siv niaj hnub no:
- Static RAM (SRAM)
- Dynamic RAM (DRAM)
- Synchronous Dynamic RAM (SDRAM)
- Ib Cov Ntaub Ntawv Tus Nqi Synchronous Dynamic RAM (SDR SDRAM)
- Double Data Rate Synchronous Dynamic RAM (DDR SDRAM, DDR2, DDR3, DDR4)
- Graphics Ob Chav Cov Ntaub Ntawv Tus Nqi Synchronous Dynamic RAM (GDDR SDRAM, GDDR2, GDDR3, GDDR4, GDDR5)
- Flash Memory
RAM yog dab tsi?
RAM stands rau Random Access Memory, thiab nws muab cov khoos phis tawj rau qhov chaw virtual xav tau los tswj cov ntaub ntawv thiab daws teeb meem tam sim no. Koj tuaj yeem xav tias nws yog daim ntawv kos rov siv tau uas koj yuav sau ntawv, lej, lossis kos duab rau ntawm tus cwj mem. Yog tias koj khiav tawm ntawm chav ntawm daim ntawv, koj ua ntau dua los ntawm kev tshem tawm yam koj tsis xav tau ntxiv lawm; RAM coj zoo ib yam thaum nws xav tau ntau qhov chaw los cuam tshuam nrog cov ntaub ntawv ib ntus (piv txwv li khiav software / program). Cov ntawv loj dua tso cai rau koj sau ntau (thiab loj dua) cov tswv yim ntawm ib lub sij hawm ua ntej yuav tsum tau muab tshem tawm; Ntau RAM hauv cov khoos phis tawj sib koom ua haujlwm zoo sib xws.
RAM tuaj nyob rau hauv ntau yam duab (piv txwv li txoj kev nws lub cev txuas rau lossis cuam tshuam nrog cov tshuab suav), muaj peev xwm (ntsuas hauv MB lossis GB), nrawm (ntsuas hauv MHz lossis GHz), thiab cov qauv tsim. Cov no thiab lwm yam tseem ceeb uas yuav tsum tau xav txog thaum txhim kho cov tshuab nrog RAM, raws li lub tshuab computer (xws li kho vajtse, motherboards) yuav tsum ua raws li cov lus qhia nruj heev. Piv txwv li:
- Cov khoos phis tawj qub qub tsis zoo li yuav ua kom haum rau hom tshiab ntawm RAM thev naus laus zis
- Laptop nco yuav tsis haum rau hauv desktops (thiab vice versa)
- RAM tsis yog ib txwm rov qab tau tshaj
- Ib feem ntau tsis tuaj yeem sib xyaw thiab sib txawv hom / tiam ntawm RAM ua ke
Static RAM (SRAM)
- Lub sijhawm ua lag luam: 1990s txog tam sim no
- cov khoom lag luam nrov siv SRAM: Cov koob yees duab digital, routers, tshuab luam ntawv, LCD npo
Ib qho ntawm ob hom kev nco yooj yim (lwm yam yog DRAM), SRAM xav tau lub zog tas li kom ua haujlwm. Vim yog lub zog tas li, SRAM tsis tas yuav tsum tau 'refreshed' kom nco ntsoov cov ntaub ntawv khaws cia. Qhov no yog vim li cas SRAM hu ua 'static' - tsis muaj kev hloov pauv lossis kev ua haujlwm (xws li kev hloov tshiab) yog xav tau kom khaws cov ntaub ntawv kom zoo. Txawm li cas los xij, SRAM yog lub cim xeeb tsis hloov pauv, uas txhais tau hais tias tag nrho cov ntaub ntawv uas tau khaws cia yuav ploj thaum lub zog raug txiav tawm.
Qhov zoo ntawm kev siv SRAM (vs. DRAM) yog kev siv hluav taws xob qis dua thiab kev nkag tau nrawm dua. Qhov tsis zoo ntawm kev siv SRAM (vs. DRAM) yog qhov muaj peev xwm nco tsawg dua thiab cov nqi tsim khoom ntau dua. Vim yog cov yam ntxwv no, SRAM feem ntau yog siv hauv:
- CPU cache (piv txwv li L1, L2, L3)
- Hard drive buffer/cache
- Digital-to-analog converters (DACs) ntawm daim npav video
Dynamic RAM (DRAM)
- Lub sijhawm ua lag luam: 1970s txog nruab nrab-1990s
- cov khoom siv nrov siv DRAM: Video game consoles, networking hardware
Ib qho ntawm ob hom kev nco yooj yim (lwm qhov yog SRAM), DRAM yuav tsum muaj lub sijhawm 'refresh' ntawm lub zog txhawm rau ua haujlwm. Lub capacitors uas khaws cov ntaub ntawv hauv DRAM maj mam tso lub zog; tsis muaj zog txhais tau tias cov ntaub ntawv yuav ploj. Qhov no yog vim li cas DRAM hu ua 'dynamic' - qhov hloov pauv tsis tu ncua lossis kev ua haujlwm (xws li kev hloov tshiab) yog xav tau kom khaws cov ntaub ntawv tsis tu ncua. DRAM kuj yog lub cim xeeb tsis hloov pauv, uas txhais tau hais tias tag nrho cov ntaub ntawv khaws cia yuav ploj thaum lub zog raug txiav.
Qhov zoo ntawm kev siv DRAM (vs. SRAM) yog tus nqi qis ntawm kev tsim khoom thiab muaj peev xwm nco tau ntau dua. Qhov tsis zoo ntawm kev siv DRAM (vs. SRAM) yog qhov nkag tau qeeb dua thiab siv zog ntau dua. Vim yog cov yam ntxwv no, DRAM feem ntau yog siv hauv:
- System nco
- Video graphics nco
Nyob rau xyoo 1990, Cov Ntaub Ntawv Ntxiv Tawm Dynamic RAM (EDO DRAM) tau tsim, ua raws li nws cov kev hloov pauv, Burst EDO RAM (BEDO DRAM). Cov hom cim xeeb no tau thov rov hais dua vim muaj kev ua tau zoo / ua haujlwm tau zoo ntawm tus nqi qis. Txawm li cas los xij, cov thev naus laus zis tau ua tsis tiav los ntawm kev txhim kho SDRAM.
Synchronous Dynamic RAM (SDRAM)
- Lub sijhawm ua lag luam: 1993 txog tam sim no
- cov khoom lag luam nrov siv SDRAM: Computer nco, video game consoles
SDRAM yog kev faib tawm ntawm DRAM uas ua haujlwm sib txuas nrog CPU moos, uas txhais tau hais tias nws tos lub moos teeb liab ua ntej teb cov ntaub ntawv tawm tswv yim (xws li tus neeg siv interface). Los ntawm qhov sib txawv, DRAM yog asynchronous, uas txhais tau tias nws teb tam sim ntawd rau cov ntaub ntawv nkag. Tab sis qhov txiaj ntsig ntawm kev ua haujlwm synchronous yog tias CPU tuaj yeem ua cov lus qhia sib tshooj ua ke, tseem hu ua 'pipelining'-lub peev xwm tau txais (nyeem) cov lus qhia tshiab ua ntej cov lus qhia yav dhau los tau daws tag nrho (sau).
Txawm hais tias cov raj xa dej tsis cuam tshuam rau lub sijhawm nws siv los ua cov lus qhia, nws tso cai rau cov lus qhia ntxiv kom ua tiav ib txhij. Kev ua ib qho kev nyeem ntawv thiab ib qho kev qhia sau ib lub voj voog ua rau ntau dua CPU hloov pauv / kev ua tau zoo. SDRAM txhawb nqa cov raj xa dej vim yog txoj hauv kev uas nws lub cim xeeb tau muab faib ua cov tsev txhab nyiaj sib cais, uas yog qhov ua rau nws qhov kev nyiam dav dav tshaj qhov yooj yim DRAM.
Ib Cov Ntaub Ntawv Tus Nqi Synchronous Dynamic RAM (SDR SDRAM)
- Lub sijhawm ua lag luam: 1993 txog tam sim no
- cov khoom lag luam nrov siv SDR SDRAM: Khoos phis tawj nco, video game consoles
SDR SDRAM yog lub sijhawm nthuav dav rau SDRAM - ob hom yog ib qho thiab tib yam, tab sis feem ntau hu ua SDRAM xwb. Qhov 'ib cov ntaub ntawv tus nqi' qhia tias lub cim xeeb ua li cas ib qho kev nyeem ntawv thiab ib qho kev qhia sau ib lub voj voog moos. Daim ntawv lo no pab qhia kom meej qhov sib piv ntawm SDR SDRAM thiab DDR SDRAM:
DDR SDRAM yog qhov tseem ceeb thib ob ntawm kev txhim kho SDR SDRAM
Double Data Rate Synchronous Dynamic RAM (DDR SDRAM)
- Lub Sijhawm hauv khw: 2000 rau tam sim no
- cov khoom lag luam nrov siv DDR SDRAM: Computer nco
DDR SDRAM ua haujlwm zoo li SDR SDRAM, tsuas yog ob zaug nrawm dua. DDR SDRAM muaj peev xwm ua tiav ob qho kev nyeem thiab ob daim ntawv qhia ib lub voj voog moos (li no 'ob npaug'). Txawm hais tias zoo sib xws hauv kev ua haujlwm, DDR SDRAM muaj qhov sib txawv ntawm lub cev (184 tus pins thiab ib qho kev sib tw ntawm qhov sib txuas) piv rau SDR SDRAM (168 tus pins thiab ob lub cim ntawm qhov txuas). DDR SDRAM kuj ua haujlwm ntawm tus qauv qis dua (2.5 V los ntawm 3.3 V), tiv thaiv rov qab sib raug zoo nrog SDR SDRAM.
- DDR2 SDRAM yog qhov hloov pauv hloov mus rau DDR SDRAM. Thaum tseem ob npaug ntawm cov ntaub ntawv tus nqi (ua ob qhov nyeem thiab ob daim ntawv sau ib lub voj voog), DDR2 SDRAM sai dua vim tias nws tuaj yeem khiav ntawm lub moos nrawm dua. Standard (tsis overclocked) DDR nco modules saum toj kawg nkaus ntawm 200 MHz, whereas txheem DDR2 nco modules saum toj kawg nkaus ntawm 533 MHz. DDR2 SDRAM khiav ntawm qhov hluav taws xob qis (1.8 V) nrog ntau tus pins (240), uas tiv thaiv kev rov qab sib raug zoo.
- DDR3 SDRAM txhim kho kev ua tau zoo dua DDR2 SDRAM los ntawm kev ua tiav cov teeb liab (kev ntseeg siab), muaj peev xwm nco tau ntau dua, qis zog siv (1.5 V), thiab cov qauv moos nrawm dua (txog 800 Mhz). Txawm hais tias DDR3 SDRAM qhia tib tus lej pins li DDR2 SDRAM (240), tag nrho lwm yam tiv thaiv rov qab sib raug zoo.
- DDR4 SDRAM txhim kho kev ua tau zoo dua DDR3 SDRAM los ntawm kev ua tiav cov teeb liab ntau dua (kev ntseeg siab), txawm tias muaj peev xwm nco tau ntau dua, txawm tias qis zog siv (1.2 V), thiab cov qauv moos nrawm dua (txog 1600 Mhz). DDR4 SDRAM siv 288-pin configuration, uas kuj tiv thaiv rov qab compatibility.
Graphics Ob Chav Cov Ntaub Ntawv Tus Nqi Synchronous Dynamic RAM (GDDR SDRAM)
- Lub sijhawm ua lag luam: 2003 txog tam sim no
- cov khoom lag luam nrov siv GDDR SDRAM: Daim npav video, qee cov ntsiav tshuaj
GDDR SDRAM yog ib hom DDR SDRAM uas tau tsim tshwj xeeb rau kev ua yeeb yaj kiab video, feem ntau ua ke nrog GPU siab (cov duab ua haujlwm) ntawm daim npav video. Niaj hnub nimno PC games tau paub tias thawb lub hnab ntawv nrog qhov zoo tshaj plaws ntawm qhov kev txhais tau zoo ib puag ncig, feem ntau xav tau cov txheej txheem loj thiab cov khoom siv video zoo tshaj plaws txhawm rau ua si (tshwj xeeb tshaj yog thaum siv 720p lossis 1080p high-resolution displays).
Zoo ib yam li DDR SDRAM, GDDR SDRAM muaj nws tus kheej txoj kab hloov pauv (kev txhim kho kev ua haujlwm thiab txo qis zog noj): GDDR2 SDRAM, GDDR3 SDRAM, GDDR4 SDRAM, thiab GDDR5 SDRAM
Txawm hais tias sib koom cov yam ntxwv zoo sib xws nrog DDR SDRAM, GDDR SDRAM tsis zoo ib yam. Muaj qhov sib txawv tseem ceeb nrog txoj kev GDDR SDRAM ua haujlwm, tshwj xeeb tshaj yog hais txog yuav ua li cas bandwidth nyiam tshaj latency. GDDR SDRAM yuav tsum ua cov ntaub ntawv loj heev (bandwidth), tab sis tsis tas yuav tsum ceev tshaj plaws (latency); xav txog txoj kev loj 16-kab ntawm 55 MPH. Piv txwv li, DDR SDRAM yuav tsum muaj tsawg latency los teb tam sim rau CPU; xav txog txoj kev 2-txoj kab kev loj teeb ntawm 85 MPH.
Flash Memory
- Lub sijhawm ua lag luam: 1984 txog tam sim no
- cov khoom lag luam nrov siv lub cim xeeb: Cov koob yees duab digital, smartphones / ntsiav tshuaj, handheld gaming systems / khoom ua si
Flash nco yog ib hom khoom nruab nrab uas tsis hloov pauv uas khaws tag nrho cov ntaub ntawv tom qab fais fab raug txiav tawm. Txawm hais tias lub npe, lub cim xeeb flash yog nyob ze rau hauv daim ntawv thiab kev ua haujlwm (piv txwv li kev khaws cia thiab cov ntaub ntawv hloov chaw) rau cov khoom siv hauv xeev dua li cov lus hais saum toj no ntawm RAM. Flash nco feem ntau yog siv hauv:
- USB flash drives
- tshuab luam ntawv
- Portable media player
- Memory cards
- khoom siv hluav taws xob / khoom ua si
Cov lus nug nquag
- Puas muaj hom RAM zoo tshaj? Tsis muaj, vim ntau hom RAM feem ntau muaj cov ntawv sib txawv heev. Tab sis rau cov neeg siv computer hauv tsev, niaj hnub no qhov kev xaiv zoo tshaj plaws nyob deb yog DDR4.
- Dab tsi yog ceev tshaj: DDR2. DDR 3. lossis DDR4? Txhua tiam ntawm RAM txhim kho nyob rau yav dhau los, ua kom nrawm dua thiab ntau dua bandwidth rau lub rooj. Qhov ceev tshaj RAM hauv cov ntsiab lus ntawm kev suav hauv tsev yog yooj yim DDR4.
