CS1 - Computer Systems - Graphics Cards

Graphics cards

Think of a graphics card as a translator, its main job is to translate binary data from the CPU as an image seen on the screen. Your computer screen is made up of millions of pixels, tiny dots that eventually build up an image. Although a graphics cards job is complex, its componants are very easy to understand. To understand the card, we can use a bit of metaphorical examples, think of the PC as an ordinary company, with an art department, when another department needs some artwork done, the art deparment gets a request, and the art department decides how to create the image and puts it on paper. A graphics card is this art department and the CPU sends information about the image or “requests” the graphics card then chooses how to use the pixels to display this image needed. It will then send this information the monitor to display it. The graphics card is placed on a slot in the motherboard, these slots can be:

• PCI-X
• PCI-Express 1.6X
• PCI
• AGP
• PCI-Express 1X

As you can see the AGP is the only brown port.

The main way of knowing which is which is by the indents, make sure the indents are the same in the slot on the graphics card. without looking at this, you will most likely break the card or the port.

It is simple, on the slot, there are two clips, if there is already a graphics card, pull these clips on the end apart and remove the graphics card. Make sure you have an Anti-static band handy, when an electronical piece of equipment is placed in here and sealed, you can be certain it will not be damaged by static electricity. When placing your new card in, all you have to do is carefully place the card in the slot and push down, this will automatically lock the card into place.


Health and Saftey must be thought about when any changes or repairs are made to a PC, Read my post on Health and Saftey

ports

Here Is a diagram of the ports found at the back of the computer.These Ports are from the cards which are connected to the motherboard.  I will go through all the ports in this post.

Power Supply: This is fairly obvious. It is where you plug the machine to the, dare i say it, power supply.

Mouse And Keyboard (PS/2): These ports were introduced, by IBM. it supports a plug with just 6 pins. Most PCs will have this port. The plugs and ports are colour coded for the piece of equipment that is going to be connected. Green is for mouse and Purple is for the keyboard.

Parallel Port: this port is mainly used to connect external devices like printers. Most PCs have this port, however recently more and more external devices have been increasing in it's USB 2.0 Connection. However if you cannot find a device that will connect to this port, you can still get Adapters to plug a USB printer to the  port.

VGA Port: this is the port which is part of the graphics cards. Obviously there is no way you can view the graphics without a monitor. This is what this port does, it connects the monitor. this is how the graphics card sends its information. Afterall all it does is change the data in the PC to a graphical format for us to use.

USB Slots: USB is frequently becoming the most commonly used port in the PC. Due to the new adaptations like USB 2.0, the port is constantly increasing in speed. now a USB port is now capable  to connect anything other ports do. It can connect external devices like Parallel Ports. it also is increasingly being used for Mouses and Keyboards too. This is the one slot you will need the most off. this is due to almost everything connecting to them, like Music Players or Memory Sticks. 

Ethernet Port: This is the connection for an ethernet cable, usually linked to the telephone line. This is your source of your local area network. It is what connects you to the internet. Increasingly Broadband Modems have been used to increase the speed of your internet, not just that but on a dial-up connection, the phone cannot be used and visa versa. A broadband modem lets both be used.

Microphone and Speaker: These are used to connect audio devices to the computer. obviously the Microphone (pink) connects a microphone and the Speaker (green) connects speakers

CS1 - Computer Systems - CD-ROM drive

CD-ROM drive

This is a device which reads information from a CD-ROM. These are fitted either externally which connect usually to a parallel port, or internally, this is fitted in a bay on the case. External drives are easier to install but have several disadvantages: they are more expensive than internal. They use up the port which may be needed for other devices like a printer, and the port itself may not be fast enough for the amount of data that pours through it. The most important factor that differs each CD-ROM drive is the speed.


A CD-ROM drive is again very easy to replace. it is usually linked with a connector and power supply cable. then make sure you remember which links into it, unscrew the old CD-ROM drive, remove it, replace it and screw the new one in. The plugs will be the same and so will any connectors.


Health and Saftey must be thought about when any changes or repairs are made to a PC, Read my post on Health and Saftey

CS1 - Computer Systems - Hard Drive

Hard Drive

The Hard Drive is one of the main features in the PC and is the main memory. The memory in a hard drive is not volatile and whenever a piece of work is saved on the PC it saves onto the hard drive.

The reason why this links into graphics is because without this the graphics is useless. Without a hard drive there would be no space for any software or even graphics itself. As RAM is volatile, you would need to start everything from scratch every time you turn the PC on.

Hard Drive Configuration and controllers.

On a PC, a hard drive can either be IDE or SATA. PC’s have many SATA ports, around 1-4, but generally there is only one IDE. You may put 2 IDE drives in one port, these will be either master or slave. Which drive that boots is defined in the BIOS which I will be getting mentioning soon.

It is generally the master that boots up or SATA1 if you are working with SATA.

The controllers which are normally places as a chipset or expansion card on the motherboard is just what its name says, a controller. It controls the transfer of data and holds any bits of information it needs to have some kind of intelligence. The controller will need to be able to communicate with the components in the computer and as time goes on it will be more critical. Most controllers are already built into the motherboard.


A Hard Drive is almost exactly the same as Installing a CD-ROM.


Replacing the master drive: Just the same as a CD-ROM. just unscrew the hard drive, remove any wires, replace the hardrive, screw it back into place and replace wires.


Adding Or Replacing a Slave drive: a second hard drive can be added to the PC.  A Slave hard drive performs in exactly the same way, whoever the master usually always has the operating system and the master always boots up first. 


Adding a slave is simple, in the case of your PC, in the right hand sight there will be a set of slots, they look more like a set of shelves. above there should be a drive already in. That is the master. 

here is an image showing you what there is, as you can see the hard drive "slots" have the CD-Rom drive slots above, which are mentioned in another post of mine, so are the power supplies, one of these hard drive "slots" should have a drive in it. when getting a hard drive you should get a hard drive in an antistatic bag and some screws. Please before you touch any components read Health And Saftey, this ensures you and the parts are safe. Hopefully once that is read you have decided to go to the measures I mentioned and are ready to tackle the task.
First you must take your new hard drive, if you are replacing the master, first remove the cables, then just remove the screws for the first drive, slide the drive out, place it in the antistatic bag and replace the slot with your new drive, screw it back in and you are done, remember to place all the cables back in. 

for a slave drive there is a few adjustments you must do to your hard drive, there is a switch on the hard drive known as a jumper. Here is an example 

Usually a key of which jumper is for which is written either on the board itself or on back of the drive.
Just switch this jumper CAREFULLY to the slave setting. then add it to the next slot like a normal master drive.

CS1 - Computer Systems - RAM

RAM

This is a type of computer memory that can be accessed randomly; to be precise; any byte of memory can be accessed without touching any other existing bytes. RAM is the most common type of memory found in computers and other devices, such as printers. There are two different types of RAM: DRAM (Dynamic Random Access Memory) and SRAM (Static Random Access Memory). The two types are different because of the technology they use to hold data, DRAM is the most common type. SRAM however is the fastest. DRAM also needs to be refreshed thousands of times per second while SRAM does not need to be refreshed, which is what makes it faster than DRAM. The reason why SRAM isn’t the most commonly used is due to it’s cost. DRAM is the cheap option.

DRAM and SRAM are both known as being volatile. This means that when the power is turned off all memory is lost. This is why you need to save work when shutting down the computer. When work is saved it is saved onto the hard drive.


RAM is simple to add and remove. First Look Over Health And Saftey then once you have gotten ready, you must open the case and look for the RAM slots, they should be fairly easy, they are usually away from the edges of the PC with two clips either side. Here is an example:

Then you must slot the bars of ram in, take notice of the notches in the slots, as you can see in this image there is a notch in the middle,  here is an image of the types of RAM, the only ones you should use is either DDR or SDR. as you can tell, these slots then only hold DDR. DO NOT try placing a bar of RAM in a slot with the wrong notches. Place your bar on the slot WITHOUT pushing it, double check the notches are correct and this is the right slot, then unlock the click by pulling them upwards or downwards, it is different for different PCs, carfully push the bar downwards, this locks the clips into place when you know it is in place. now you know it is safe. When removing, just unlock the clips and this will unlock the bar of RAM. remember to store it in an antistatic bag.

CS1 - Computer Systems - Microprocessor (CPU)

Microprocessor

Otherwise known as CPU. This is the heart of a computer, they are also found in all digital devices whether it’s a clock radio to a specialised system in cars.

There are 3 characteristics that a microprocessor has, these are:

Instruction set: this is the set of instructions that the CPU can perform.

Bandwidth: the number of bits processed after a single instruction.

Clock Speed: This is measured in megahertz (MHz), the clock speed defines how many instructions the processor can perform each second.

These characteristics is what usually determines which is better. Therefore a 64-bit CPU that runs at 50MHz will run better than a 32-bit CPU that runs at 25. 


It is advised not to remove the CPU due to the fragility of the CPU.

CS1 - Computer Systems - Motherboard

Motherboard

This is the main circuit board of a computer. The motherboard contains the connectors for attaching additional boards. The motherboard typically contains the CPU,BIOS, memory, mass storage interfaces, serial and parallel ports, expansion slots and all the controllers required to control devices like a CD-ROM drive etc. All the parts of the motherboard are known as the chipset. Additions to the motherboard includes extra memory chips which can be added to the motherboard directly, you can also upgrade to a faster PC by replacing the CPU chip entirely. Anything else and you probably will need to replace the whole motherboard.