I've never done it but I don't see why it would be a problem. Since you say you want to set it up as a slave, I'm assuming you have your RAID array with IDE drives. If it's jumpered correctly then it should be recognized by the OS as another drive. I'm not sure how advantagous it would be though. If i'm not mistaken, RAID 5 uses striping to obtain better performance and I think it would be better to leave the paging file on the faster RAID array rather than a slower slave disk.