TYPES OF RAM MEMORIES
The RAM (Random Access Memory) is the main memory of a device where informative programs and data are stored. it is also known as volatile memory, that is, the data is not permanently saved, which can be rewritten and read constantly.
There are different types of RAM, which have different characteristics, among which are: DDR: known as SDRAM (Synchronous Dram), This memory interleaves two or more internal memory arrays so that while accessing a matrix, the other is being prepared, it allows reading and writing data at twice the speed buz. DDR2: These allow the input / output buffers to operate at twice the core frequency, allowing 4 transfers to be made during each clock cycle.
DDR3: they are twice as fast as the DRR2 memory since it could transfer data at an effective clock rate of 800-2600 MHZ.Cache memory or RAM cache: it is a part of high speed static RAM memory (SRAM), it is a special high speed storage system. DRAM: this memory is of the asynchronous type, that is, they go at different speeds than the system, and their refresh times were quite high, but also quite slow. SDRAM: They are a type of synchronous memories, that is to say, they go to the same speed of the system, with some times of access that in the most recent types.
SDR: these modules perform an access per clock cycle, their memory bus speed ranging from 66MHz to 133MHz. VRAM: The same can be accessed by two different devices simultaneously. This allows a monitor to access the VRAM for screen updates at the same time a graphics processor provides new data.
SIMM (Single In line Memory Module): consist of a small printed circuit board that stores memory chips, and that is inserted into a SIMM socket on the motherboard or on the memory board. DIMM (Dual In line Memory Module):uses a 168 pin connector. Can not mix DIMM and SIMM.
DIP (Dual In line Package): stores a memory chip in a rectangular box with two rows of connection pins on each side. SRAM (Static Random Access Memory): is faster and more reliable than the most common DRAM (Dynamic RAM). FPM (Fast Page Mode): Access to memory bits is done by means of coordinates, row and column. EDO (Extended Data Output): is a type of dynamic RAM chip that improves the performance of Fast Page memory mode by around 10%.
PB (Pipeline Burst): is a category of techniques that provide a simultaneous process in parallel within the computer, such as overlapping operations moving data or instructions in a conceptual ‘pipe’ with all phases of the pipe processing simultaneously. Then I leave a small table so you can see more detailed some of the things that I explained earlier of the RAM momimas.
|TYPE OF MEMORY ||PIN NUMBER||DIMM||FREQUENCY||BITS|
|FPM DRAM,||72 Pin||SO-DIMM|
|EDO DRAM||72 Pin||SO-DIMM||Different speed|
|SDRAM||100 Pin||DIMM||At system speed|
|SDR SDRAM||144 Pin||SO-DIMM||64 bit|
|SDR SDRAM||168 Pin||DIMM||66MHz-133MHz||64 bit|
|DDR SDRAM||172 Pin||MicroDIMM||64 bit|
|DDR SDRAM||184 Pin||DIMM||100MHz-200MHz||64 bit|
|DDR SDRAM||200 Pin||SO-DIMM||64 bit|
|DDR2 SDRAM||200 Pin||SO-DIMM||64 bit|
|DDR3 SDRAM||204 Pin||SO-DIMM|
|DDR2||240 Pin||DIMM||100MHz-266MHz||64 bit|
|DDR3 SDRAM||240 Pin||DIMM|
|FB-DIMM DRAM||240 Pin||DIMM|
|DDR2 SDRAM||244 Pin||MiniDIMM||64 bit|
The Ram Memory technology uses a synchronization signal to perform the read / write functions so that it is always synchronized with a memory bus clock, unlike the old FPM and EDO memories that were asynchronous. The entire industry opted for synchronous technologies, because they allow the construction of integrated systems that operate at a frequency higher than 66 MHz.