(Dynamic RAM DRAM), .. , . - ( ) DRAM (access time ~70 ). , , - ( , ). (refresh rate), . . 2 . - .
DRAM :
(interleaving mode). , . (). , . () ;
(fast paging mode FPM).
. ; , , . . () , ( ) RAS (Row Address Select) . , CAS (Column Address Select) . () RAS. . , .. ( ).
, . (recharge time), 90% . RAS, ( 2 ). 60 . 33 .
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() (extended data output EDO). EDO 10-15% , FPM. . 50 .
, (burst mode BEDO). EDO. , SDRAM . 66 ;
- SRAM (CDRAM Cache DRAM EDRAM Enhanced () DRAM). , 4 DRAM 16 SRAM;
SDRAM (Synchronous DRAM), , . , , . , , .
, - . ( ) , . , , , . -. , . , .
SDRAM DRAM 4 , EDO 50%. 100 /. 100 .
SDRAM: DDR (Double Data Rate) SDRAM ( SDRAM II), ESDRAM (Enhanced SDRAM), - 22 , 12 , 133 .
Intel Pentium-IV RAMbus: RDRAM, 600 600 / DRDRAM (Direct RAMbus DRAM), 800 1,6 /.
SIMM (Single In line Memory Module - ), DIMM (Dual In line Memory Module) RIMM, RAMbus.
DIMM SIMM , ( 72 168) , , ( Pentium 64-) . DIMM (double sided) SIMM. DIMM- SDRAM -, , , SPD (Serial Presence Detect), .
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( ) DIMM ( SIMM).
(Read-Only Memory ROM) () .
, , (non volatile) .
( ), - (-) (PROM Programmable ROM).
, . (EPROM Erasable PROM). EPROM . . - . . . , . (12), . 50 , 300 , 10
Flash ROM ( EEPROM Electrically EPROM), . 1-2 , 100
FLASH- BIOS, , " ".
1 . 1 32 . - : , - .
, , , , - , .. - BIOS (Basic Input/Output System) () , , , . 128 - 256 .
