The components that make up a computer are called hardware. These include a motherboard, central processing unit, random access memory, and storage devices.
The CPU handles digital instructions, and its speed determines how fast a computer can work. A GPU handles graphics and video, and it can be added as an expansion card or integrated into the processor.
Motherboard
Motherboards provide a single platform for all components in a computer to connect to each other. They have traces that lead to slots into which the central processing unit (CPU), random-access memory (RAM), and expansion cards are plugged in. The motherboard also has sockets that can connect to hard drives and front panel ports via cables and wires.
It also contains a clock that keeps track of time and manages the interaction between different pieces of hardware. It has a BIOS that handles the built-in operating system for the machine, and it provides electrical power to all connected parts of the computer. Many of the aforementioned devices generate heat, and the motherboard has a cooling fan that removes it. It can contain multiple RAM slots, as well as PCI-E x16 slots for graphical cards such as Nvidia or AMD Crossfire. It may also have a SATA slot for hard drives.
Graphics Card
A graphics card (also called a video card or graphics processing unit) handles rendering images, videos and animations for display on your computer monitor. It works with the central processor unit (CPU) to process and output visual data. A high-powered graphics card is essential for gaming, video editing and other graphic-intensive applications. A discrete graphics card is a separate piece of hardware that plugs into a PCI or agp expansion slot on the motherboard. It has its own RAM and requires a more powerful power supply than integrated graphics chips.
Discrete GPUs are replaceable, so you can upgrade them as newer technologies become available. The amount of VRAM a card has determines its performance level; 4 gigabytes of memory is sufficient for most gaming purposes, but you can get even more if you need to support high resolution games or use other demanding applications. Graphics cards may be reference or custom-designed, with the latter having modified designs and cooling solutions to offer improved performance.
Hard Drive
A hard disk drive (or HDD) is a non-volatile data storage device that uses magnetic recording to store and retrieve information. Most modern internal HDDs use multiple platters inside a solid enclosure that spin rapidly, and they have read/write heads that move over the surface of each platter to record and read digital data.
Each platter is divided into sectors that represent one or more bits of data. The heads magnetize portions of the platter to represent these bits, and then the drive electronics transfer the data to and from a computer.
The platters and heads are supported by a light, stiff arm that moves the head assembly across the spinning disks very quickly. The arm can be positioned over the disks up to 50 times per second. The movement of the read/write heads over the platters is controlled by a mechanism called the actuator, and the data is transferred by thin printed circuit cables.
RAM
When you play a video game, the data that your computer’s central processing unit (CPU) needs is loaded into RAM. The CPU can then access that data quickly when it’s needed. Once the game is closed, the data in RAM is cleared and replaced with new information.
Nonvolatile system storage like hard drives doesn’t lose its data when power is cut, but volatile RAM does lose its data if the computer shuts down. To avoid this, RAM is always connected to a power source to keep each memory cell’s electrical charge charged.
Today, most desktop PCs use SDRAM (synchronous dynamic RAM). This type of memory connects to the computer’s clock to speed up operations. DDR SDRAM — the kind used in most modern desktops and laptops — operates at twice the speed of regular SDRAM and includes on-die error correction code to prevent corruption. It also consumes less power, so it’s a great upgrade option for older computers.