You didn't say what OS your after but just use generic drivers, quick look these are the main 3 your after

Chipset: 790FX northbridge / AMD SB750 southbridge
LAN: Marvell 88E8053
Audio: Realtek ALC885 7.1

The Asus M3A79-T is based on the same chipset and very similar Marvell 88E8056 network card. You could cheat and just use it's drivers. Sound may work as well, not sure

You didnt say which OS your after, if

Asus M3A79-T

Oh sorry, primarily Windows XP, but I'd take any, whatever is available. So you say these are really just generic drivers, nothing customized by DFI for the specific board? Thanks!

Yes you can use generic drivers, the only difference might be a different Logo when you run the setups, (DFI might have a DFI logo, Asus an Asus, MSI a MSI, etc) otherwise there is rarely any other customization of the actual drivers between motherboards using the exact same hardware....
added: you can still direct DL the Marvel LAN driver and the Realtek audio driver for XP .
https://www.marvell.com/support/downloads.html# Category = Marvell Public drivers, Part number = 88E8053, Apply. choose one ;p
https://www.realtek.cz/download-ALC885-sound- … wsXP-32bit.html
https://www.realtek.cz/download-ALC885-sound- … wsXP-64bit.html
The AMD 790FX chipset driver for XP seems a bit different, maybe due to MS wanting all old OS drivers removed...

Did you get the XP drivers ?

Thanks, I was able to download the generic drivers that you all suggested and they seem to work well indeed.
I found the exact chipset driver on https://www.driveridentifier.com/scan/ati-pci … 1002%26DEV_4349 which I hope is the original one indeed.