SATA Ports not working

Please help!!!

Ok I have a Dell XPS 430. The mobo as far as I know has 5 sata connections on it. There are two right beside the RAM and the 3 further down the motherboard.

I want to install a second drive. The problem is that nothing will work when I plug it into my bottom 3 ports. The top 2 are being used by the primary factory drive and the optical drive.

Now I switched the optical for the new hdd to see if my drive was the problem. I boot windows and it comes right up. I got it from a friend and it worked fine without any need for formatting.

So my question is a) can I use the other 3 sata ports? and b) if not what are the ports used for?

Thanks in advance