What is Ram? What specifications does RAM have? This article will answer the above questions.
1. RAM (Random Access Memory)
RAM is random access memory (the access speed to memory cells is the same), has fast access speed, can read or write data into RAM.
This memory only stores data temporarily when the computer is running. These data is deleted when power off computer.
The structure of RAM consists of many memory chips. Each memory chip is made up of millions of transistors and capacitors. A transistor and a capacitor combine into a memory cell that stores bit 0 or 1.
Capacitors often discharge power, so they need to be recharged (refresh) in a certain period of time, when the power is lost, the data on the memory chip will be lost.
2. Types of RAM
There are 2 types of RAM:
- SRAM (static RAM)
- DRAM (dynamic RAM)
SRAM (static RAM)
SRAM stands for Static Random Access Memory. Static RAM is expensive, fast access speed. For example, cache memory.
DRAM (dynamic RAM)
DRAM stands for Dynamic Random Access Memory. It stores bits as an electric charge in very small capacitors and must regularly recharge the electric charge for DRAM, called refresh.
The access speed of DRAM is slower than static RAM (SRAM).
There are 2 main types of DRAM:
- SDRAM stands for Synchronous Dynamic RAM. SDRAM includes SDR, DDR, DDR2, DDR3, DDR4.
- RDRAM stands for Rambus Dynamic RAM. They usually used in servers.
Types of RAM are connected to the mainboard through RAM slots with different design standards. References: Types of RAM slots on the motherboard
3. Specifications of RAM
RAM capacity is the ability to store data on a RAM memory chip, measured in B/KB/MB/GB.
Bus speed is the operating frequency of RAM or the number of data accesses of RAM in 1 second.
Bandwidth is the amount of data that can be accessed from RAM in 1 second.
For example: A RAM stick reads: 256 MB DDR – 333MHz – PC2700 (256MB capacity – DDR RAM type – 333MHz bus speed – 2700 MHz bandwidth).
