It all depends on what motherboard you have.
In my case, the line I put in was:
To find out what chipset your motherboard uses type lspci and look for a line talking about your IDE interface.
if you cd into:
You will see a list of all the available drivers. Choose one that looks like the line in your lspci and put that filename (minus the .ko extension) as the first line in the file /etc/modules.
Hopefully thats easy enough to follow, I don't tend to make a good teacher!