I know this is an old post, but I'm currently looking for the drivers myself, and this thread was one of the first that popped up on Google. So hopefully this helps someone out in the future.
Unless you have a USB adapter for the network, you'll need a flash drive to sneaker net some files from a network connected system. I will write directions as per USB transfer as most wont have an adapter.
Please do not attempt this if you have 0% of an idea on what's going on. I assume if you're here looking for a driver you are able to navigate websites and installations properly. I will do my best to give guidance but downloading drivers can be a bit dangerous if you download the wrong thing, leading to possible viruses.
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Finding your Network Card<<
First off, We need to check what Network Card you have. Download Aida64 from
Here. Just click on the Aida64.com Mirror. Transfer this exe over to the system having an issue. run the program,
make sure to click off ANY extra installations, downloads etc. Once the program is up, we'll want to look under [Devices] then [Physical Devices]. In this list you should see something along the lines of:
> Bus 0, Device 25, Function 0 Intel 82578DC (Hanksville-D) Gigabit Network Controller
This is the card that is installed on my DX4831. If yours happens to be the same, go Here, select your OS and download the latest drivers. during install, uncheck the Intel Proset stuff, only "Drivers" should be checked. Otherwise Continue with the next steps.
The actual card may change but it should still say "Network Controller" in the description. NOTE: THIS IS NOT 100%, SOME COMPUTERS WILL JUST SAY GENERIC NETWORK CONTROLLER INWHICH YOU'LL PROBABLY NEED THE MANUFACTURES/A TECH'S HELP.
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Installing the card<<
Now that we know WHAT we need to install, take not of the number (pen/paper, phone pic) and head back to the network connected system. At this point you should be able to google the card plus "driver" (Intel 82578DC driver is all I typed). Be sure NOT to click on any ads that appear on the top. If it's an intel card the first result or two should be "downloadcenter.intel.com" for the url and a pretty obvious title ("Intel 82578 Gigabit Ethernet PHY - Download Center" for me) Click here and select your OS. download the latest drivers (normally a zip or exe file) to your flash drive and head back to the crippled system. you can normally just run the Setup (either the exe file if one, or the SETUP file in the zip folder) straight from the flash drive, but you can copy it to the desktop if you're worried. during the installation, if it gives you a choice on WHAT to install (in my case it wanted to install the Intel PROset software, I recommended, unchecking anything that is not the basic driver for the card.) Give it a bit to install, and restart the system AFTER IT IS FINISHED (thought a restart may not be needed, it's generally recommended).
And there you have it. At this point the network card should start behaving normally. Hopefully this helps someone at some point.