Wireless ethernet and card reader Drivers for Dell Latitude D820

it is simple : enter your service tag on that page - then it will show YOUR downoads

here is how i handle unknown devices :
if you have  unknown devices in device manager, you can use this procedure to identify them :

1-visit the motherboard manufacturers support site, for downloading drivers
2- use windows update >optional updates to find them

3-Start>Programs>Accessories>System Tools>System Information.
Now select  "Components" and highlight "Problem Devices".
All hardware devices with a driver problem will be listed here.
Make a note of the first line of the PNP Device ID line of the entry. It will show a Vendor number and a Device number (VENxxxxDEVxxxx) both four digits long.
Look up those numbers here:   http://www.pcidatabase.com/index.php

This will tell you the manufacturer and the chip number.  
Check the manufacturer's website first or google them - or post them here

If your LAN is running, you can also use windows update> optional drivers, or  use slimdrivers : https://www.slimwareutilities.com/slimdrivers.php

Dear , can you download from the WEB SITE  dell support .and install items  the Chipset ,management .system Utilities

http://www.dell.com/support/troubleshooting/us/en/555/Product/latitude-d820


.Otherwise you can find even multi Driver CD From cd s shop  Thanks