Hi there,
I'm assuming you mean the KT7AR, so I'll jump in. You are correct in your assumption that you don't need to use RAID to use the additional IDE controller. I have the KT7R, which is essentially the same board.
You still need to load the Highpoint controller driver, in order to use those IDE channels. Just because you load the driver does not mean you HAVE TO use RAID. I just had one HD as Master on one of those channels for the longest time.
You will then have 4 IDE channels, each capable of having a Master and Slave device on each one. This should be plenty, especially if you're not running a RAID array. Hope this helps.