Old Computers Needed!

Hey everyone, I need some help!
I need some ideas on where I could find some old-ish (eg. winXp with a dvd drive) Computers, either for free or for cheap!


The only place I can think of right now is the tip shop, but I doubt they will have any ones that arnt totaly ancient.

The reason why I want some old computers is because I want to practice making/cleaning/upgrading a old computer before I do it with my own ;)



Thanks everyone!!

Peripheral: Optical mouse

The optical mouse was developed by Agilent Technologies and was released in early 2000; these mice, rather then using a ball, use a tiny camera to take around 1,500 pictures every second. (These mice are able to work on almost any surface because of the small, Redlight-Emitting Diode (LED) that bounces light off almost any surface so the camera can detect the surface of E.g., a glass table)

The mouse then sends each picture to a Digital Signal Processor to check if the surface has changed / moved from the last picture. Based on the change in pictures the (DSP) determines how each of the images differ from the last and then works out how far the mouse has moved. The mouse then sends this information to your computer and your computer then moves the mouse! Its quite amazing how fast this works, as the mouse takes hundreds of pictures per second to make this work and appear to move smoothly on your computer!

[tutorial] Computer parts and what they do [Hard Drive]

The hard disk drive is the main and largest data storage device in your computer. Everything on your computer is stored here, The OS (operating system) and all of your files.

The hard drive is sometimes referred to as the "C: drive" mainly because Windows designates the 'c' driver letter to this primary partition on the primary hard drive in a computer by default.

What is an external hard drive?

Think of an external hard drive exactly like your normal hard drive but working outside your computer. Both are extremely similar. Normally, they can be connected to your computer via a USB connection. If you have a 'pen drive'(also known as a USB stick),they work like a miniature external hard drive in the sense that they store date in an external format; an external hard drive is just like a large key-drive.

[Tutorial ] Computer parts and what they do. [Peripheral]

Peripherals are quite simple. If you do not know what a Peripheral is they are any hardware items that are connected internally or externally to a computer and are used in data transfer for example:

*keyboards

*speakers

*printers

*game controllers

*microphones

*mice

*monitors

[Tutorial ] Computer parts and what they do. [BUS]

SA collection of wires through data is transmitted from one part of a computer to another. You can think of a bus as the highway on which data travels within a computer. 


Looks like this: 
http://i.shopbot.com.au/n_4993/a7/f3/c77c793e478e3519770ef21ee78df3a7.jpg


From shopbot.com.au

[Tutorial ] Computer parts and what they do. [Memory/ram]

RAM stands for Random Access Memory. It is what you are actually using at any one time. Let me try to explain it this way. Your brain has a conscience and a sub-conscience memory. The conscience memory is what you are using right now. The sub-conscience memory is what you will you need to remember something that happened a long time ago [this would be the hard drive/hard disk].

When you access your sub-conscience memory, then those memories are transferred to your conscience memory. Think of a computer in the same way. The hard drive is the sub-conscience memory, so to speak. When your computer turns on, then what it needs to run your programs is then transferred to the RAM, or conscience memory of your computer.

When you are finished with a program or application, and you close the program, then it is wiped out of the RAM in order to make room for more applications, but it stays on your hard drive so you can recall it later. Same goes for when you turn off your computer. Eg. when you go to sleep.

[Tutorial ] Computer parts and what they do. [Motherboard]

A motherboard is also known as a main board, system board and logic board. Motherboards can be found in a variety of electrical devices, ranging from a TV to a computer. Generally, they will be referred to as a motherboard or a main board when associated with a complex device such as a computer, which is what we shall look at. Put simply, it is the central circuit board of your computer. It is the 'brain' of the computer. All other components and peripherals plug into it, and the job of the motherboard is to relay information between them all. Despite the fact that a better motherboard will not add to the speed of your PC, But it is important to have a motherboard that can process information fast enough to keep up with the information it is given.