What Are the Basic Computer Hardware Components?

A central processor, random access memory, a hard drive and peripheral devices are the basic computer hardware components. The motherboard connects them all together and acts as the brain to allocate power throughout the system.

Today, most PCs use x86-based processors, and most of them run Microsoft Windows. Alternatives to Windows, however, include the Mac platform from Apple (running macOS) and free, open-source Unix-like operating systems.

Processor

The processor is the brain of a computer, telling everything from the disk drives to the graphics card and screens what to do. It is also known as a central processing unit (CPU). There are many different processors from manufacturers like Intel and AMD, but they are usually grouped into families that understand the same instructions.

There are four primary functions of a CPU: fetch, decode, execute and write back. Fetch is the process of retrieving an instruction from memory, decode is where the instruction is translated into signals that control other parts of the CPU and execute is when the instructions are carried out.

Inside the CPU there are also components called cache memory that store copies of data that are frequently used, avoiding the need to retrieve it from main memory. There is also an arithmetic logic unit (ALU) that performs basic and advanced arithmetic and logic operations.

Memory

A computer’s memory, like a desk, allows multiple tasks to be performed at once. Data stored in primary storage — RAM — is accessed immediately, while files saved to secondary storage – hard disk drives — require the CPU to thumb through the information in sequence.

The CPU accesses memory according to a hierarchy that prioritizes the quickest and easiest to read or write data. As the amount of data stored in a system increases, the hierarchy changes to accommodate more and larger pieces of data.

Until recently, most computers used dual in-line memory modules (DIMMs). To install DIMMs, the motherboard must be equipped with matching slots or “banks,” and the modules themselves are notched at one end to prevent them from being installed incorrectly.

Hard Drive

The hard drive is where all of the computer’s data is stored. The hard disk has a special magnetic layer where each bit of information is recorded as either a 1 or a 0. This data is then read or written by the reading/writing heads that “float” above the surface. The heads read and write data by writing an electric field on the surface of the platters, causing the magnets to change their polarity based on whether they are passing over a 1 or a 0.

The disk platters themselves are made from aluminum or glass-ceramic, both of which require energy-consuming processes for production. Other materials such as the disk enclosures and printed circuit boards use a variety of other materials, including prepreg (a type of fiberglass), copper, and copper-nickel alloy, which all use energy for processing.

Graphics Card

The graphics card processes and renders graphical data to the display, making it one of the most important components in your computer. It interfaces with the motherboard via an expansion slot, such as PCI Express (PCIe) or Accelerated Graphics Port (AGP).

A dedicated GPU is more powerful than integrated graphics and has a higher resolution. Its memory is separate from the main system RAM, and it usually has a faster refresh rate.

Dedicated GPUs are available in many price ranges. NVIDIA’s GeForce line of cards are popular among gamers, while AMD’s Radeon series offers strong competition. To see the type of GPU in your computer, click the Start button and then open System Information. The left navigation pane will show a list of all connected displays. The GPU will be listed here as well, along with a number of other specifications.

Motherboard

Motherboards are the central hub connecting a computer’s functional components so they can interact. They have sockets for different parts of the system like the CPU, RAM and expansion cards, as well as ports for external devices.

The central processing unit is plugged into the motherboard, and the motherboard communicates with this part through data buses. These data buses provide high-speed movement of information between different components, making the computer run smoothly.

Some smaller computers use a different type of board called a logic board instead of a motherboard. While this board works the same way, it is soldered into place so that the component can’t be removed and replaced later. This saves manufacturers time and money as they don’t have to assemble the individual hardware parts individually.