So is a RAID card at all any good for this PC. Don't forget I am using it for both gaming AND media. What would the RAID card do and what are the modes?
Your choice of motherboard comes with SATA RAID onboard, offering two modes when you have 2 SATA hard drives installed:
RAID 0 - Stripes data across 2 drives, which can be accessed in parallel and so increase performance. Performance benefit is only noticeable in video editing applications.
RAID 1 - Mirrors a drive's contents on second drive. Pure backup, no performance benefit.
Alternatively, you could just have two separate drives with no RAID enabled.