video and audio driver problem

A friend of mine found a computer and he reformatted it, but he doesn’t have the drivers for it, most importantly of course the video drivers. So how does he know which driver to download off the internet? He installed windows 2000 professional on it but it is currently running in 16 color mode because of no video card driver.
Does he just have to open it up and see? And if so how would he go about doing this meaning where is the video card on the pc and what if it is an onboard video card. Also he doesn’t have the audio driver for it either. Both the video and audio drivers in Device Manager have a question mark of course because windows did not find any.

Any help would be great, thanks for your time.

Provided is AGP or PCI can use tool to get the PCI Vendor and PCI Device IDs (two sets of digits). The IDs may be displayed as a single (combined) number. Can then lookup the Vendor (Manufacturer) and Device (Model) digits to identify the card.

Can ID the cards here
http://www.pcidatabase.com/

Page also has links to software for getting the IDs.

Of course this holds true for all PCI cards and not just video. And AGP uses same scheme as PCI.

For audio, some older systems have integrated ISA sound, so this may not work for sound. ISA has PnP and there are similiar tools and EISA ids for ISA PnP. Not all ISA are PnP, but would have to be fairly old sound chip to not be PnP.

Of course by card I mean chip, as the IDs are from the chips and not card, so same holds true for integrated video that is on the motherboard and not on a card.