System Hardware Component: System Memory (RAM)

Memory is a data storage element that uses on/off states on a chip to record patterns of binary data. An on value represents 1, and an off value represents 0.

Memory is classified into two basic types Static and Dynamic. Static memory (also known as nonvolatile memory) doesn’t require power to maintain its contents while Dynamic memory (also known as volatile memory) requires power to maintain its contents.

An example of static memory is ROM (Read-only Memory) which is the integrated chip and can store data permanently. These chips are used in system to store BIOS settings in order to permanently saved. The below diagram shows the ROM chip for BIOS.

Figure: ROM chip for storing BIOS

Random Access Memory (RAM)

As its name implies that the processor can access the data stored in the RAM randomly at any time from any location in the memory. The RAM has further two types Static RAM (SRAM) and Dynamic RAM (DRAM). Static RAM (SRAM), also called flash RAM, is the type we can use it when we store files on a USB flash drive. Static RAM is nonvolatile memory as its contents are maintained. Dynamic RAM is volatile; when we turn off our computer, its content is gone. Generally the memory on the motherboard is DRAM and we usually call it simple RAM. RAM is used to store the data temporarily for the processor and when the system is turned off then all of the data in it is erased automatically.

Figure: Random Access Memory (RAM)

Memory Bus Speed

The pathway that delivers data to and from the memory is called a memory bus. The memory bus has a speed, which determines how quickly data will travel on its pathway. The system timer determines the speed at which data enters the processor. There can be different kinds of memory speed. When memory operates at the same speed as the front-side bus of the processor is called single data rate (SDR) synchronous dynamic read-only memory (SDRAM).

When memory operates at the double, triple or more speed as the front-side bus of the processor is called double data rate (DDR) synchronous dynamic read-only memory (SDRAM).

The DDR1 has double data rate as SDR and half power consumption.

The DDR2 has four times data rate as compared to SDR.

The DDR3 has eight times data rate as compared to SDR.

So we can say that the DDR3 is the fastest in speed and lowest in power consumption among all.

The following figure shows the shapes of three DDR family RAMs and notice the difference in the lengths of their notches which actually differentiate them.

Figure: Different types of RAM according to their speed

Shape and form factor of RAM

There are various sizes and shapes of RAM modules for PCs . The memory chips arranged on a small circuit board is the dual inline memory module (DIMM). The dual in DIMM means that the module has pins on both sides of the circuit board. PC desktop uses normal DIMMs while laptops use the smaller versions of it like small outline DIMM (SODIMM) and the difference between their size and shape is shown in the following figure.

Figure: Two different form factors of RAM i.e.

This was all about the primary memory of the system which is simply known to be the RAM. We will talk about the secondary memory in the coming blogs.

So, thanks for giving your time to Read…!!!

One clap, two clap, three clap, forty?

By clapping more or less, you can signal to us which stories really stand out.