Well done on a big fail !.
Do you have any Idea how many computers are out there?.
Running different motherboard and chip set types on them?.
And how exactly do you intend to get the driver if the Ethernet adapter has no driver installed to connect to the internet to get it in the first place ? Bump!
Add to the fact you need to detail what motherboard you have Brand: and it`s model number.
Where exactly did you put the driver dvd that came with the computer or all the disks that came with it ?. Dig them out.
Try them, because the drivers will be on them somewhere if you look.
Or set a side in a partition of the Hd, in a folder saying Drivers. If you take look at the HD drive, browse its contents. You will no doubt find them there.
If the system is a configured system by Dell,HP ect. Obviously the case since you do not even know the name, or model number of the motherboard in the Pc. Logic is all it takes.