Both integrated RAID controllers (one is PATA and the other SATA) on one of my main boards can be set to ATA or RAID (the PATA controller) and BASE or RAID (SATA) depending on whether you just want to use extra drives not in RAID arrays or drives actually in RAID arrays. You haven't told us whether your BIOS has such additional settings. If it does and it is set to RAID theoretically the controller might refuse to 'see' your drive because you have only one drive attached which is not sufficient to do anything useful on a RAID controller. And of course it might not work because it may be set to SATA-2 which might not work on the controller as I have suggested twice already. Why haven't you run the Drive Feature Test?

It would help if you told us which Hitachi drive exactly you are working with.

And if the BIOS setting has become too messed up just reset the defaults with F7 and start from there again. With the defaults most things should work. Just check whether the integrated peripherals need to be enabled after the defaults have been set.

And this main board doesn't hide by any chance the more advanced settings until you activate them as the main board of mine I mentioned does? It only shows me the 'advanced' settings after I press CTRL-F1. And I had to actually read the manual to find that out.