Lecture 2.2 - Computer Components

Lecture 2.2 - Computer Components#

Motherboard (MB)#

A computer cannot exist without a motherboard, much like you cannot send signals around your body without a nervous system.

A motherboard is the main circuit board inside a computer that connects the different parts of a computer together. It has sockets for the CPU, RAM and expansion cards (e.g. discrete graphics cards, sound cards, network cards, storage cards etc)… and it also hooks up to hard drives, disc drives and front panel ports with cables and wires. While you have not been introduced to all the different components that plug into a motherboard, this course aims to introduce you to the most popular choices on the market.

Hard Drives (HD)#

As mentioned previously hard drives contain the data of your computer. From lecture 1 you can recall how quickly technology advanced and in a similar sense, data storage advanced as well. The two most common ways to store data on your computer today include hard disk drives and solid state drives.

Hard Disk Drive#

A traditional hard disk drive (HDD) uses spinning disks to read and write data. The disks are coated with magnetic material and are read by a moving read/write head. Data is stored on the disk in the form of magnetic patterns and because the disk is spinning, the read/write head needs to move to the location on the disk where the data is stored.s. Think CDs, DVDs, and Blu-Rays, but the discs staked on top of each other (a platter), and an actuator arm that reads all of the discs simultaneously to read and write data.

Because these types of hard drives spin on the inside, they are sometime referred to as “mechanical hard drives”. They come in 3.5 inch and 2.5 inch form factors (sizes) and are very dense in storage.

Solid State Drive#

A solid state drive (SSD) and a hard disk drives (HDD) are both types of storage devices that are used to store data, but they work in very different ways.

A solid state drive (SSD) uses a different technology than an HDD; instead of a platter, SSDs use memory chips. There are no moving parts in an SSD (or the memory chips), which means that data can be read and written much faster. Additionally, since the data is stored on memory chips, an SSD is much more durable and less likely to be damaged if dropped or bumped. SSDs are more expensive per GB than HDDs, but they are faster, and more reliable, which means they can offer a better performance and long-term value to the user.

Data Storage#

Data in your phones, computers, and other piece of technology is dictated by bits (B) and bytes (b). This course covers more in-depth topics on the differences of bits and bytes in a future lecture, but mentioning it here as it relates to hard drives is important to remember.

When purchasing hard drives, keep in mind that most hard drive manufacturers advertise their drives in bits. Meaning you can go to a BestBuy or MicroCenter (or online) and you can find hard drives from sizes as small as 256 GB to 18 TB. However when plugged into your computer, it does not read 256 GB and instead reads something smaller. That is because of the bit and byte difference that is explained later.

Central Processing Unit (CPU)#

A CPU is the brain of a computer. It is responsible for executing instructions, or code, that make up a program. It retrieves the instructions from memory (RAM or Hard Drive), decodes them, performs the necessary calculations, and stores the results. These results can mean the true zero’s and one’s that make the decisions of you left-clicking with your mouse or tapping on your phone.

In simple terms, It’s the heart of the device that does all the calculations and runs the software.

Random Access Memory (RAM)#

RAM, or Random Access Memory, is a type of memory that is used to temporarily store data that the CPU needs very quick access to. When a program is running, the CPU retrieves the instructions from the storage device, such as a hard drive, and loads them into RAM. The CPU then reads the instructions from RAM and performs the necessary calculations and store the results.

However, RAM is volatile memory which means when the device is shut off the data stored in it gets lost, that’s why the data is stored in hard drive or SSD, which is non-volatile.

Power Supply Unit (PSU)#

A power supply, also known as a PSU (power supply unit), is a component in a computer that converts alternating current (AC) electrical power from the wall outlet into direct current (DC) power that the computer can use. The power supply then distributes the DC power to the various components of the computer, such as the CPU, RAM, and storage devices, similar to how our blood helps delivery oxygen and other nutrients around our body.

On a more technical level, a PSU regulates the voltage and current to the various components of the computer, providing the necessary power to run the system, and also providing over-voltage and over-current protection, keeping the components safe from damage. The power supply also manages the power distribution throughout the system, providing more power to components that need it and less power to components that don’t. This helps to ensure that the computer runs efficiently and doesn’t waste energy.