RAM is a volatile memory, it is stopped when the power supply, lost its memory. Therefore, the data stays in RAM while the computer is turned on. RAM is much faster read and write, can be compared to other storage media such as hard disks, CD-ROM, diskette, RAM, etc., both read and written, so it is sometimes referred to as read / write memory.
There are two basic types of RAM:
(a) Dynamic RAM (DRAM)
(b)Static RAM (SRAM)
(a) Dynamic RAM (DRAM): Dynamic Random Access Memory is the most common type of RAM that stores each one bit of data in a separate capacitor and a transistor. Capacitors tend to leak electrons, thus there is a need for recharging. Therefore, DRAM, SRAM, in contrast must have refreshed his memory cells or given an electric charge every few milliseconds. This refresh requirement operation is from where dynamic RAM gets its name. DRAM is a volatile memory becauseit loses data when the power is switched off.
DRAM's structural simplicity gives it an advantage over SRAM. It consists of only one transistor and one capacitor per bit, the basis of which it has a very high density. SRAM, on the other hand, requires six transistors.
There are three basic types of DRAM:
(i) Synchronous DRAM (SDRAM): While all other types of DRAM work asynchronously to the system clock, Synchronous Dynamic Random Access Memory, a type of DRAM,synchronizes itself with the microprocessor clock speed. It is a sort of RAM that is twice as fast as EDO DRAM. The speed of SDRAM is rated in MHz than in nanoseconds. SDRAM chips are mounted on DIMM memory modules. These memory modules are in accordance with the CPU speed, which they are intended to support classified to.
(ii) Rambus DRAM (RDRAM) Rambus Dynamic Random Access Memory is a type of synchronous dynamic
RAM developed by Rambus Corporation. It is a highSpeed memory technology, the transmission of data up to 800 MHz. Since narrows the RDRAM memory bus to 16-bit systems get more speed by using parallel channels. RDRAM has heatsinks paid to heat that is a major issue with RDRAM. Production of RDRAM is expensive compared to other RAMs
RDRAM memory modules (RIMM) can be used only on the motherboards specifically designed for them. A 16-bit and 32-bit RDRAM RIMM have 184 and 232 pinsrespectively.
(iii) DDR-SDRAM: stands for Double Data Rate Synchronous Dynamic Random Access Memory. It is a type of memory integrated circuits used in computers. DDR transfers data over the bus over both (rising and falling) edges of the clock, doubling the data throughput over that of standard SDRAM. DDR memory runs at bus speeds of up to 400 MHz. DDR memory chips to 184 -pin DIMM modules installed. Is DDR SDRAM consumes less power, thereforebest suited for laptops.
b () static RAM (SRAM): Static Random Access Memory is the kind of RAM that its data without external refresh, as long as the force has still applied, unlike DRAM, are being updated at regular intervals. It is a kind of memory that is faster and more reliable than DRAM (dynamic RAM). Since Static RAM operates on the principle of motion of electricity, it is a fleeting memory.
There are three basic types of Static RAM (SRAM):
o asyncSRAM: Short for asynchronous Static Random Access Memory. It is an older type of SRAM, which works independently of the system clock that is asynchronous.
o Sync SRAM: Short for synchronous Static Random Access Memory. This kind of memory is synchronized with the system clock. The SRAM is more expensive.
o Pipeline Burst SRAM: This is the commonly used memory. Pipeline means larger packets sent back into memory at once and willacted on very quickly. This type of SRAM can operate at bus speeds greater than 66 MHz.
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