Installation
After purchasing your new graphics card, you need to know how to install it. This shouldn't be a frightening task, not everything computer related is complicated, you can learn to do this on your own.
1st Step
The first thing you have to do is figure out whether you have a PCI or AGP graphics card slot, which will determine the type of card you will be purchasing. To figure out what kind of graphic/video card you have you are going to right click on "My Computer" and click Properties. Click on the hardware tab and you should see a button labeled "Device Manager," go ahead and press that button. A fairly big list should pop up showing you several icons, click on the icon labeled "Display Adapters," now right click on the video card icon and click properties. Check the location of the "Bus" and now you know what kind of slot you have.
2nd Step

Your going to have to get inside the computer so you are going to want to remove the side panel/casing, this should be a fairly simple screw mechanism (pretty tough stuff, stop me if it gets too complicated). You should see your existing graphic/video card or a metal casing that needs to be removed.
3rd Step
Remove the existing card by gentle sliding it out, replace with new graphics card and plug in the alternate power source that is located close to the card slot. The power source shouldn't be hard to find since it is the only slot that will fit the cord.
4th Step
Install the software. Reboot your computer. Get Blown Away!