3. The Motherboard

Some people say the motherboard is the most important part of the PC, which makes sense as everything that runs, runs through the motherboard at some point. However, other people would argue that the CPU is the most important component as it is the 'brains' of the machine. Either way both of them may leave a little hole in your wallet.

This is the layout and picture of my old mobo MS-6577 v4:




Note: All modern PCs are based on the original IBM AT Motherboard from 1984.

Once you have chosen your motherboard, you will want to choose a CPU. To do that you need the CPU socket type as shown below:


Here is another list, of CPU sockets: CPU sockets - CPU-world.com. I'll come back to the CPU in the next post.

The motherboard sets or dictates the performance of your system. There is a set of two chips on the motherboard called the northbridge {closest to the CPU}, and the southbridge {usually located around the PCI or add-on slots}. Together they are called the chipset. On this motherboard the northbridge chip is Intel 845GE and the southbridge chip is Intel CH4:


The northbridge {or memory controller hub} controls the fastest components on the motherboard such as the CPU, RAM {memory}, and video card slot. Whereas the southbridge {or I/O (input/output) controller hub} controls the slower components like the USB, hard drive expansion slots and system clock. {I will give the full list as I go along, lets stick with the motherboard and chipset for now.} As the term controller hub suggests, these two components are the hubs where control of the other components occur. The northbridge helps the CPU communicate with the other faster components I mentioned, whilst the southbridge helps the slower components.

Note:As the northbridge works the hardest with the other hardest working components so it gets hot, for that reason it has a heatsink of its own.

The southbridge dictates which technology you can have for your system, like the newest technology or even just the basics like USB and firewire.

2. The Case

I have an old PC that is not working any more, so I will be using pictures {not the best pictures but I am no good with the camera!} of that as it comes apart, so you understand what's going on.

The case or main unit {which houses the computer components/parts: motherboard, CPU, etc.} needs to be chosen carefully. Cooling of your system is an important factor, as well as if your components will actually fit. Ok so lets look at the front of a case first.

The Front

1. Indicator lights for the power and drive activity


2. USB, firewire and audio ports/sockets


3. 2 bays for CD-ROM/DVD drives


4. 2 bays for a floppy disk drive


5. A vent

Note: Not all cases will have the ports/sockets/features I have listed and shown in the picture above, so make sure you select one that has everything you want/need. {You will see the front vent on my computer when i take the PC apart as I go along.}

The drive bay covers {Disk drives} are easy to snap in and out {Although my case has hinged covers that do not need to be removed to gain access to any new disk drive - check yours before breaking it}. The second bay in my PC is not actually in use so I'll get a picture later to show you.

Cases or chassis, are generally metal and have removable panels. The vents are for warm air to flow out of the machine whilst the fans are to suck cool air into and around the machine. It is important not to let them get clogged up with dirt/dust. These are two newer cases with vents and fans in different arrangements:


The Sides


Both sides are the same, they have this one small vent, this was enough five years ago when I bought the computer. But today's PCs need better cooling systems with bigger vents and fans, as we expect more from our technology and internet.

If you are going for a top/new system you should use a Thermally Advantaged Chassis {TAC - This may or may not be used as a real term, I just typed it to make life easier} {or "Prescott Ready", "Chassis Air Guide 1.0/1.1"}. Intel recommend no less than TAC for their Pentium 4 CPU and above {Gaming and high end machines will need this}. As you can see below from Intel's sketch, it has a tube on the inside of the side panel. This is to guide air directly to the motherboard and CPU {I'll write about them later} but for now you should know they are the two most expensive of all the components/parts:


The Back

1. PSU with main fan


2. More sockets/ports


3. Another fan {This is over the motherboard}

Note: Some cases come with a power supply unit {PSU}, but if you are building your own machine you are more than likely going to build a higher powered machine for the same price as a lower powered machine ready built from the shops. So you may want to upgrade the power supply or buy a case without a power supply {we'll talk more about that later}.

The fan/vent openings need to be large like they are. The openings should be 60% or more - {So if you have a fan which has more than 40% of the 'openings' covered by a bit of metal showing the case companies logo, that is not good!} You should go for fans at least 92mm for todays machines, so keep that in mind when selecting a case. Some people cut more openings in their case, but it depends how brave you are.

I will come back to this post once I have taken the PC apart, and show you the inside layout of a case. For now I will explain what else needs to be taken into account when choosing a case.

You need to consider the case's compatibility with the components you will be using.
A term that is used a lot is 'form factor'. This is the size and shape of everything.
So the screw holes in the case need to match up with the screw holes on the motherboard, and everything needs to fit, basically. {The screws and standoffs you need usually come with the case.

Case Form Factors

There are two main form factors: ATX {Advanced Technology eXtended} and BTX {Balanced Technology eXtended}. BTX being the newest. However the ATX form factor remains top for build-it-yourself'ers. Most components {RAM, Power supplies, CPU and other connectors} can be mixed but ATX motherboards are for ATX case's and BTX motherboards are for BTX case's.

I will get a picture of both style cases so you can compare the two layouts, for now here is the inside of my ATX case with all the components still in:

1. Eazy.as.aPC

This blog is for anyone that has tried to learn about computers, but just can't quite get their heads around it.

Everything is as simplified as possible {for my brain}, so if you can't understand this, then i'm sorry but there may be no hope for you or me!

Ok,lets get serious. I am guessing that you own/have access to a computer with internet connection or you wouldn't be reading this blog!

I will be writing about building PC's more than anything else so if that's not what you want...tough {joke} not.

By the way, just to be clear this is a basic PC system that you can get from shops today:


Note: The computer in the picture above has no relevance to this blog it is just an example.

OK lets get started