You have an LSI software RAID chipset. I don't know the model. If you want RAID to work as it should you should invest in a hardware RAID card via
www.3ware.com or even LSI's hardware RAID offerings. I know it sucks, but these are the things you need to investigate before you buy the hardware. Software RAID on linux is shit because vendors do not release their drivers as GPL aka in the kernel itself. The exceptions are LSI's hardware RAID and all of 3ware's line of cards.
As it is, if the drivers are not in the kernel(GPL'd), then you will have a life of pain awaiting you. You will be stuck using specific distro's that are compiled for a specific kernel if you are lucky. If you aren't lucky- which is your case- you get squat. You can get a 2 port SATA RAID hardware card with GPL drivers integrated into the kernel from
www.3ware.com. www.pricewatch.com and
www.pricegrabber.com can get you the cheapest price on whichever card you choose. Sorry, but your motherboard is made for windows. Good luck.