Hard Drive Not Detecting

I have a Hitachi Deskstar HDS722516VLAT80 hard drive (160GB), and the bios does not detect the drive at all. I've made sure my jumper settings are all correct, but the drive is still not detected. It might be that I accidentally deleted the system files on that disk, but even if I did, shouldn't it still detect?

I also found a site where I can get all the files. http://www.hitachigst.com/hdd/support/download.htm
The problem is that I do not know which file to download. I need the tool that helps make my hard drive work.

I am also absolutely sure that my hard drive is not physically damaged. Before the hard drive had the detection problem, it had worked perfectly, but I probably modified some of the system files on the hard drive accidentally.

Before the problem, I remembered that the total capacity of my hard drive was 127/128GB, even though it is a 160GB hard drive. I am assuming that my bios or system cannot detect hard drives over 128+GB, so maybe that is why my hard drive does not detect. Maybe that is the problem.

If anyone has any ideas to get the hard drive to work, please help! I have no ideas as to how to fix it.
If it is easier to help me on AIM and if you have some questions that you want to ask, I am online on AIM (sn: stinkytofu3) (I am invisible)

Thanks

Before the problem, I remembered that the total capacity of my hard drive was 127/128GB, even though it is a 160GB hard drive. I am assuming that my bios or system cannot detect hard drives over 128+GB, so maybe that is why my hard drive does not detect. Maybe that is the problem.

More than likely that is the problem. Could be your chipset will not support such large capacity as well.. Update your BIOS and try it.