Anyways, I imagine with a new motherboard (and therefore a new RAID controller), the RAIDed hard drives would not be recognized by the RAID controller. In this case, the RAID would need to be re-done, which would require the hard drives to be reformatted, and therefore the data would be wiped. A major disadvantage of RAID 0 is that the data stored on the hard drives is very easily lost through hardware failure. This is why it is not recommended to store any important data on a system employing RAID 0.
However, RAID 0 isn't all bad... It can increase performance pretty substantially. With two hard drives splitting the reading and writing work, you should theoretically get an 100% performance increase. Of course, this isn't the case because they have to wait for the RAID controller to tell them what to do. The better the RAID controller, the faster this will get accomplished. Another limiting factor is that files that are smaller than the stripe size aren't broken up, and therefore experience no performance benefit.
But anyways, my point is that if you are willing to risk your files, or able to back up the important ones regularly, then RAID 0 might be an acceptable risk for the performance benefit.