"Software" vs. "Hardware" RAID.
I think your card (HPT370-based) is "Semi-Software", like "Win Modem" is semi-software. But, for ease of use, just refer to it as "Hardware". Essentially you treat it like a fancy IDE controller, and as such, set up the RAID sets in "BIOS"-like manner, before booting OS.
The creation of RAID sets is external to Linux, Windows or Other. However, the manufacturer has the RAID tools for Linux for this particular controller on the web site. (see link bellow) Ideally, Linux will never know it is booting from a virtual RAID drive. With "software raid" (of which you probably have all the HOW-TO's) linux itself bunches up the IDE channels to create RAID disks. The key to hardware RAID: (a) easier to install OS onto
RAID set and (b) less load on CPU.
For your card, the best approach is to follow the directions in the HPT's driver package. GO here
to "Linux Source Code" section. Get the latest version package, and look for readme.