PRIMARY STORAGE DEVICES PART-1

Hi All,

In computer storage devices are devided in to 2 types .
Those are

1.primary storage devices .
2.secondary storage devices.


     First Let's know something about primary storage devices.RAM and ROM(Read Only Memory).RAM (randam access memory) It is a volatile memory (means requires power supplycontinuously) andit is a temporary memory.  it is divided into 2 types those are


1)SRAM (Static RAM)
           It is cache memory.two types of cache memory present those are L1 & L2
L1 (Internal Memory with in the mother board)
L2(External Memory ) when your buying a Mother Board L2 cache like this 1MB,2MB,4MB etc.

2)DRAM(Dynamic RAM)

          In DRAM various models are present.Those are
SD,DDR1,DDR2,DDR3,EDO        Let's know ...

SD(Synchronous Dynamic)

    The RAM 68 PINS and it's capacity is 32MB -512MB.5V POWER SUPPLY NEEDED.IT HAD A SINGLE NOCH AND 2 CUTS.

 DDR1 (DOUBLE DATA RATE)

    THE RAM 128PINS AND CAPACITY IS 2GB.IT HAD A 2NOCHES AND SINGLE CUT.CUT IS AT RIGHT SIDE.

 

 DDR2

    THE RAM  256 PINS AND CAPACITY IS 4GB AND 3.5V POWER SUPPLY NEEDED.CUT IS IN THE MIDDLE.

DDR3

   THE RAM  512 PINS AND CAPACITY IS 8GB AND 3.3V POWERSUPPLY NEEDED.THE CUT IS AT LLEFT SIDE.

 EDO(EXTENDED DATA OUTPUT)

   IT IS USED IN SPARC MACHINES.

NOTE:    In the upgradation of RAM two points are considered.
             
               1.Storage capacity should be high.
               2.power utlization should be less.