2lostinohio - It also possible to use software RAID5 built-in into Windows Server. Also it is possible to patch Windows XP to get this functionality. In general there are 3 type of RAID controllers:
1) Hardware - prices starts from 300$, more than mobo
2) Hardware/Software - price about 30-40$
3) Software - built-in into Windows Server, or *nux.
The second type is rubbish, because all calculations of checksum made by supplied drivers. You can use it as SATA port extender (if you don’t have enough on the mobo), actually it is a port extender with small BIOS and set of drivers.
I suggest to use 1 option or 3. Please note, if you use Windows Software-RAID, you can migrate from one mobo to another without any problem. But if RAID-controller died - you will have to find exactly the same model in order to restore data.