In this video from ITFreeTraining I will look at the basic parts of a motherboard. Understanding
the different parts of a motherboard is important for passing the CompTIA exam and also essential
when troubleshooting motherboards.
The best way to start learning about motherboards is to have a look at one. Motherboards need
to meet the same standards and so will be designed in similar ways. For this video I
will look at a Gigabyte motherboard. By knowing what to look for, you will be able to look
at any motherboard and be able to identify where certain components are. If you have
trouble finding them, the motherboard manual will usually have a diagram showing where
all the components are. The diagram will make it easier to find components on the motherboard.
First, I will look at the CPU socket. The CPU socket has changed over the years, but
it should be easy to spot. It is a large square shape. The CPU socket is keyed so the CPU
will only go in one way. You will find in modern computers just about everything is
keyed nowadays to prevent a plug or component being plugged in incorrectly.
In later videos I will look at putting a computer together, including putting the CPU in. Essentially,
the CPU goes into the socket without any force and once in place the lever is moved, locking
the CPU into place.
Next, I will look at the expansion slots. The expansion slots, as the name suggests,
allows the computer functionality to be expanded. Anything from a video card, sound card, RAID
cards and network cards to name a few, can be plugged in an expansion slot.
The slots are color coded and keyed. Keying essentially means that only the one connector
can be put into the one slot or plug. It is like not being able to put a square peg into
a round hole. In the case of expansion slots, the keying prevents the card being installed
the wrong way or into the wrong slot. For example, PCI and ISA are keyed differently,
so only a card of that type will go into a slot of that type.
Manufacturers of motherboards are free to use whatever color they want for each expansion
slot. There is no common standard. You will generally find that similar slots will be
the same color. In the case of this motherboard, blue is for PCI express by 16. The small white
slots are for PCI express by one and the longer white slot is for PCI. The ‘by’ in the
name refers to the number of lanes or lines of traffic going to each expansion slot.
In some cases, the same types of slots may be different colors for other reasons. For
example, I have seen motherboards where a PCI express by 4 slots are a certain color
and the PCI express by 16 are a different color. With this motherboard, you can see
that the locking clip is different on PCI express slots. On this motherboard, this indicates
the top one is ‘by 16’ and the next one is ‘by 4’. Motherboard manufacturers are
free to design the motherboard any way they want, use any locking clip they wish and any
color. When you start looking at a motherboard, look for these little subtle things, as placing
a video card in the wrong slot may mean it will underperform if it works at all.
Next, I am going to look at the IO area. This is usually at the back of the computer and
is used to connect devices and peripherals to the computer. For example, USB, audio and
network. In the older days of computing, there was only a few standard connections that were
found on all computers. For example, keyboard, serial and parallel connections.
As computers developed, the number of connections required increased and different motherboards
supported different features. For example, one motherboard may support a speaker mic
plug only, while another may have six plugs for surround sound.
For this reason, it is impossible for computer case manufacturers to support every configuration,
so an area on the motherboard is dedicated to connectors. The motherboard manufacturer
is then free to use this space as they see fit, but they will need to supply their own
custom IO/Shield.
The IO/Shield is placed between the connectors and the computer case. It prevents dust and
electromagnetic interference from entering the case. In some cases you will find that
the motherboard manufacturer may provide two or more IO/Shields. These may be different
colors or in some cases hide some of the connections if they are not required. Despite the fact
that the IO/Shield may change in color and design, the connectors will always be found
in the same place on the motherboard.
On modern motherboards, you will most likely have a number of SATA connectors. On older
motherboards you may also have IDE connectors. On a server motherboard you may have SAS ports.
Generally, they will be in and around the same location, but motherboard manufacturers
are free to place these where they like.
In some cases, particularly with SATA ports, they may support certain things. For example,
a certain SATA port may support SATA 3 while the others may support only SATA 2. Certain
RAID functions may require storage devices to be plugged into certain SATA ports.
In some cases, the motherboard manufacturer may make the SATA connectors different colors
to make it easier to determine which are which, however this is not guaranteed. This motherboard
has printed on it a number to indicate the different SATA ports. Most motherboards will
have something printed on them to help you determine which port is which. It can be difficult
to see, otherwise if you look in the motherboard manual this will tell you which port is which.
The next connectors I will look at are on the front panel header. This allows the computer
case to be connected to the motherboard. This includes things like the power switch, reset
switch, indicator lights and the PC speaker.
Since different cases come with different features, the header allows the cables to
be plugged directly into it. If the computer case does not support it, you simply don’t
plug it in. Of course, things like the on/off switch you will need to plug in and all computer
cases come with that.
To determine which connectors are connected where, most motherboards will have writing
next to the header. It is quite small and difficult to read; otherwise you can find
the information in the manual. For connectors like switches, it does not matter which way
they are plugged in; however, lights and the PC speaker need to be plugged in the correct
way. To determine which way to plug the connector in, the negative wire will either be black
or white. With this particular computer case all the wires are black. When this is the
case, you will need to look at the plug to determine which is the negative and positive
wire.
On modern motherboards, generally the connectors will be in a header like the one shown. On
some older motherboards, you may find the connectors are spread out over the motherboard
and not in a header like the one shown.
There will also be other headers on the motherboard. In the case of this motherboard, most of them
are close together. However, these headers can be found anywhere on the motherboard.
If you have trouble finding a particular one, have a look in the motherboard manual.
Each of these are keyed so the cable cannot be put in the wrong way. You will notice that
certain pins are missing. If you have a look at the plug for the cable, the missing pin
will be blanked out. Different headers will have different blanked-out pins; this prevents
even cables with the same number of pins being put into the wrong plug. If you find that
a plug does not go into the motherboard, check the pins on the plug. It may be the wrong
plug or the cable is upside down. If you find you are having to use force, you most likely
are trying to plug it in the wrong connector.
Next, I will look at the memory slots. You will find that memory slots are next to the
CPU. Each slot is given a number, usually printed on the motherboard. When installing
memory, it is important to ensure it is installed in the right slot. Some motherboards will
not work unless a particular memory slot has memory in it, usually slot 1. In some cases,
the slots will be color coded. Generally, placing memory in the same color slots will
allow it to be used together giving a performance increase.
The next connectors I will look at are the fan connectors. There will normally be a number
of these around the motherboard. The connectors will be either three-pin or four-pin. The
three-pin uses voltages to control the speed of the fan. The four-pin connectors use the
extra pin to control the speed of the fan.
A three-pin connector will plug into a four-pin connector. Nowadays, a motherboard will generally
detect which type of fan has been connected. On some devices like video cards, if you plug
a three-pin fan into a four-pin connector it will not work. You will know it does not
work because the fan will spin at full speed the whole time. If this occurs, replace the
three-pin fan with a four-pin fan.
On your motherboard, all the fan connectors may have the same type of connector and support
three- and four-pin connectors, however you should take care to plug the fan into the
correct connector. For example, you could connect the CPU fan to a connector that is
labeled system or power fan. This will work; however, the BIOS or UEFI will detect the
CPU fan is not running. If you ignore this error, the computer will treat the CPU like
a case fan and may not spin it at the required speed to cool the CPU. So, it is a good idea
to connect these correctly so they are reported correctly and also function correctly.
The last connector I will look at is the power connector. Your motherboard will have one
or two of these connectors. Older motherboards will only have the P1 connector which is 20
or 24 pins in size. Newer motherboards will also have a P4 connector. This will either
have 4 pins or 8 pins. Like everything else, it is keyed so you won’t be able to plug
it in the wrong way.
This covers the basic parts of a motherboard. In later videos, I will look into these topics
in more detail. Until those videos, I would like to thank you for watching.