The motherboard or main board or even system board will be the first thing that you want to put into your case. Most all motherboards will come with the correct screws that you need. Along with the correct back panel plate that you need to make sure that once you get it installed it looks nice and neat. This board is the ASUS P4T motherboard. It has a 4x AGP slot (accelerated graphics port) which also supports AGP Pro cards. If you will notice the long brown slot in the middle of the board. That is where your video card will go if it is AGP. I will talk more about video cards on the video card section. To the right of the AGP slot there are five identical slots. These are called PCI slots (peripheral content interface). This is where you will stick most of your peripherals such as your modem, sound card and so on. Now lets take a look at the big white square in the middle. That is where the Pentium 4 processor will go, it is a 423 pin processor and it will only go in one way. Other processors, such as some of the Pentium III processors and the Athalon processor will actually have a long slot instead of a square that they fit into, but you will not have to worry about that since it will be the biggest slot on the board. To the left of the white square, you will see 4 long slender slots. These are where you will install you memory or commonly known as RAM (random access memory) This particular board only uses one type of memory and that is RDRAM (rambus dynamic random access memory). When you install RDRAM each chip that you install is called a RIMM (rambus inline memory modules). With RDRAM you have to have all of the slots filled in order for it to work. This motherboard came with two CRIMMs (continuous rambus inline memory modules) These basically fill in the slots and carry the information through the empty slot to another slot where the memory is. The great thing about the Pentium 4 is that it supports dual channel memory, which basically means that since there are four slots for RIMMs instead of using one channel at a time it uses two channels of memory so you will get 3.2GB per second memory bandwidth instead of 1.6GB per second. How this works is that there are four slots, two of the slots are on one channel and the other two slots are on another channel. (e.g. if you have four 128MB RIMMs installed you will have 512MB of memory and you will be using both channels to get 2x faster bandwidth).
The white rectangle in the very upper left part of the motherboard is where you will plug in your power supply. To the right of that you can see 3 slots, one of which is blue, and one of the black slots is shorter than the rest. The two longer ones are your IDE connectors. The blue one is what you will typically plug your hard drive into and the black one is what you will use for your optical drives. The short black slot is where you plug your floppy disk drive into. Now if you will take a look at the bottom left corner of the board you will see a pink connector. This is your parallel port where you will plug your printer into. There are also two PS2 ports that you will use for your mouse and keyboard, and there are also two serial ports which you may also use items such as a mouse or keyboard on. This mother board has four USB ports (universal serial bus). Two of which are one the motherboard, and the other two are on card that you will put into one of your tower's expansion slots, this card is called a bridge. USB is the standard now days. Printers, mice, scanners, digital cameras... use USB, you can even network through USB just like you can through a serial port or parallel port.
That pretty much sums it up for the motherboard, there are a ton of more things to learn about it but I tried to keep this section as short as possible, because this could be a whole web site all by itself. Just keep in mind the main places where you will install all of your hardware, after all it is very easy, everything is made so that it will only go in one way and will only fit into its own particular slot.
I give the ASUS P4T mother board a 95% on overall greatness. This motherboard scored such a high rating because of it's dual channel memory, the fact that the instructions go into great detail about everything and most of all it's Jumper Free Mode, which allows you to overclock the system components with ease without ever opening up the case the change jumpers around. It also shuts itself down if the processor starts to overheat. This product would have scored a 100% if it had Integrated LAN (local area network), so I would not have had to purchased an Ethernet card. This motherboard cost me about $300