The card will work fine. It supports all ATA hard drives - and optical too. If you do get it, you have to set the BIOS boot order to "SCSI" before the regular hard drive. The Promise is categorized as a SCSI card.
Did you check in BIOS Setup to be sure that 48-bit LBA (large block addressing) is enabled?
When your PC was first made, there were no drives bigger than about 75GB. They had no way of knowing that drives would get this big - or they didn't want to spend the bucks getting ready for it. The most likely reason is the latter.
You may be able to partition the remainder in Windows and use it as D. Give it a go. If not, you will need the card.