how to get drivers for your computer without system CD

If you ever format a computer then you will need the drivers for your system ,these are usually video ,sound ,network and others ,missing a driver CD makes this even more difficult.
If you have a branded PC like HP then all you have to do is go to their website and download the appropriate drivers for your computer.
No name brand computers are more difficult you have two options.
1: Use a program to view your manufacturer like Hwinfo,
2:You will have to open up the box and look on the motherboard itself to find out the manufacturer and model of your computer.
Here is a video to help you;http://www.youtube.com/watch?v=COCuW6mS6EQ
If you have other devices connected to your system like a printer ,webcam etc. ,their drivers and software will also need to be downloaded from the manufacturers site or use the CD if you have it.