via bus master ide drivers

I have a new pc running winxp pro with two 40gb hardrives, when I start up I get a message that it is not working and that I am missing the “VIA bus mastering IDE drivers”, can anyone give me some insight as to a fix for this. I am going to be setting up a mirror raid, but am waiting for drivers and a fix for that problem as well.
Please help!
Thanks,
Dave