Short Bytes: A motherboard acts as a platform for establishing connections between various components that are essential for the successful operation of a computer. A printed circuit board houses all the components, either soldered or connected discretely through expansion slots. A motherboard can also be defined as the basic building block of a computer.
A computer comprises of many components like the CPU, monitor, keyboard, mouse, and much more. All these components talk to each other via a common hardware known as the motherboard or simply mobo. Most users don’t have much idea about the green colored thing placed inside their machine. So, the question, “What is a Motherboard?” sounds obvious to the ears.
Over the years, I have evolved from a naive computer user to the one who knows something about the electronic devices which make our lives easier. I’ll try to elaborate the knowledge that I’ve gained about what a motherboard is and what are the components of a motherboard? So, let us dive into the world of motherboards.
What is a Motherboard?
A motherboard is basically a printed circuit board used to connect different parts of a computer like the central processing unit, memory, printer, mouse, keyboard, graphics card, and other peripherals through physical slots and interface connectors. If you’ve ever opened up your machine, you might’ve observed different lines going in various directions. These lines constitute a circuit used to allow communication between different hardware devices attached to the motherboard. Electrical signals carrying data information pass through these lines. The flow of current in the printed circuit board is similar to a normal circuit, though, less in voltage. The advantage is that it can be accommodated in less space than the conventional one.
History of Motherboard
The development of motherboards has been parallelly propelled with the advent of microprocessors–your regular CPU chip like Intel Core i5–in computer machines. Before the microprocessors, the computers housed multiple PCBs which were connected to each other through a backplane. A backplane is a parallel arrangement of electrical connectors, each of them aligned with the other such that every pin from a connector gets linked with the relative pin of the other. This backplane was used to connect multiple PCBs together. Components like the central processing unit (CPU), memory, and other peripherals were connected to different PCBs and then combined using the backplane.
Over the time, with microprocessors coming into existence, these backplanes became a thing of the past and various components were integrated directly into a single Printed Circuit Board. Thus, a single PCB, termed as Motherboard, was only required for a computer.
In the 1980s, companies like Apple and IBM released the documentation and blueprints of their motherboards. This was intended to allow the production of replacement motherboards for their popular computers like the Apple II and the IBM PC. The motherboards began to become more consolidated but complex at the same time. Super I/O (single ICs) chips started to exist in the motherboard in the late 80s, allowing support for low-speed peripherals like mouse, keyboard, floppy drive, etc.
As the clock started approaching the millennium year, the need for expansion slots was eliminated for the components like video, storage, audio, and network adapters by embedding them into the motherboard. Currently, the motherboards have taken a leap to a stage where almost negligible changes can be made after a motherboard is manufactured. The size of the motherboard has reduced drastically since the last few decades and may continue to shrink down further.
Form Factor is the term given to the shape and size of a motherboard. Generally, all types of motherboards are designed according to predefined specifications creating a similarity between the motherboards manufactured by different companies. However, the size may differ to a small extent from brand to brand.
ATX, developed by Intel, is the most widely used configuration specification for desktop motherboards which is implemented by almost all the major manufacturers.
MiniPC is a form factor specification given for small sized computers like the Apple Mac Mini and Intel NUC. These machines are used for basic computing needs like web surfing, word processing, video playback, etc. Though, the advancement in technology has made these machines more than an internet surfing device.
What’s inside a Motherboard?
After having a look at how motherboards have evolved over the years, we will now have a look at the components of a motherboard.
These are the long slots attached to the motherboard to install DIMM chips to the computer. DIMM stands for Dual Inline Memory module which consists of DRAM integrated circuits. The Dynamic Random Access Memory (DRAM) is a volatile memory that stores the data and files being executed by the CPU. Many variants of DRAM exist like DDR, DDR2, DDR3, DDR4.
Earlier machines, between the 1980s and late 1990s, used SIMM (Single Inline Memory Module) type memory modules.
You might’ve heard terms like LGA 1150 or AM3+. Getting the correct socket type for a processor is a common dilemma faced when we assemble a computer, for example, a desktop machine. So, what exactly a socket is? A socket is a place where the microprocessor or CPU sits on the motherboard. Due the socket, a microprocessor doesn’t need to be soldered to the motherboard. We can remove it anytime as per our will.
The type of sockets used are:
LGA (Land Grid Array) – In this, the pins are present on the socket.
PGA (Pin Grid Array) – In this, the pins are present on the CPU chip.
ZIF (Zero Insertion Force) – In this, while inserting the CPU chip the contacts on the socket are made loose by lifting a lever. Thus, the CPU gets fitted easily.
The LGA type sockets are mainly used by Intel whereas, AMD uses the PGA-ZIF type sockets. Let’s take the example of Intel, they make many socket variants. The difference comes in the pin arrangement. That’s why we have to be very careful while deciding the CPU and socket type.
It is an IC present on the motherboard that is responsible for the creation of a communication channel between the CPU and various components like memory, and peripheral devices connected to the motherboard. Without a chipset, all the different parts will not be able to talk to the central processing unit and this will directly affect the performance of the computer. Chipset consists of two parts:
Northbridge which is directly attached to the CPU through the front side bus (FSB). It uses the memory controller to contact the RAM chip to transfer data between CPU and RAM. In addition to this, it also establishes communication with the PCI Express bus.
Southbridge links to the USB ports, SATA interface. It doesn’t directly report to the CPU, all the information has to pass through the northbridge before reaching the CPU.
The basic operation of a clock generator is to synchronize the operations of different components of a motherboard. It generates a clock signal that jumps between high and low frequencies, thus creating a metronome for the coordination of actions. I won’t jump into its depth to tell you the technicalities.
Expansion Card Slots
You might be familiar with the term PCI (Peripheral Component Interconnect). It is used to install additional components like Wireless adapters, graphics cards, etc. PCI is an expansion bus that is used to transfer data between the computer (i.e. CPU and RAM) and the connected peripheral device.
A bus can be understood as a path through which the data travels. The term refers to both the software and the hardware required to transfer data. A bus has two parts, the address bus which passes the information about where the data should go, and the data bus which carries the actual data to be transferred.
Modern motherboards include the PCIe (PCI Express) slots which are an upgrade over the conventional PCI and PCI-X expansion bus standards.
Motherboards are equipped with connectors for attaching storage devices like magnetic hard drives, optical drives, and SSDs. These devices work through an interface known as SATA. SATA or Serial ATA is also a computer bus that enables connection between the storage media and the computer through the host bus adapters present on the motherboard.
Various SATA versions namely, SATA 3.2, mSATA, eSATA, etc exist and are used depending on the configuration of the machine. For example, mSATA or mini-SATA is used for SSDs and hard drives installed in laptops.
Computers have a main power supply unit but it is not possible to deliver power to all the components directly from it. Hence, power connectors are used to distribute the power from the main supply to various components like RAM, CPU, chipset, and expansion cards.
Some modern expansion cards like the high-end graphics cards require more power which can’t be provided by the main power connectors of the computer. So, these graphics cards come with their own power connectors to get the right amount of electrical power.
Motherboards also have Flash ROM which a non-volatile memory chip uses to store the BIOS of the system. Apart from these, additional components like the USB (Universal Service Bus), disk controllers, ethernet controllers, etc. exist on the motherboard. Modern motherboards also have on-board graphics chips (like Intel HD Graphics) and sound cards which are directly soldered on them. The internal graphics cards are capable of handling the basic graphics processing of the machine and provide video output through VGA and HDMI ports.
Improper temperatures in case of motherboards may lead to a reduction in performance and lower life expectancy over the course of time. Hence, various devices like the heat sink and cooling fans have been designed to bring down the temperature when the heat is generated by the motherboard’s components.
The ideal operating temperature for motherboards is around 45-degree celsius. Your computer won’t be happy with you if you don’t equip it with an appropriate cooling system, raising the temperature above intolerable limits. You might have heard about frying of motherboards due to high operating temperatures.
So, that’s all I know about Motherboards. If I have failed to include some major point, please let me know in the comments section below.