[Rob]

Ok, let's check out some real basics. When you reinstalled windows, did you also run, just after the windows installation, any CDs that were supplied with your computer's motherboard?. Often those will have drivers specific for your computer. If there is a choice run the general chipset one first, then work down the list.

If you check control panel > System then on the pop up system properties window, click hardware and Device Manager, do any devices, especially the network ones have a yellow exclaimation or red cross? If so you haven't got something enabled, and so do need to identify the right drivers for them. Those should be on a CD that came with your computer, alternatively copies might be available on the manufacturer's support sites for your computer or it's components.