I deleted the raid and made a new one and that seems to have fixed it. My read numbers doubled, and now they seem to be in line with what other people have reported with two Samsung 830 SSDs. Move raid-sets between motherboards probably isn't a good idea
However, I think the setup on my old Gigabyte motherboard did something strange, or more likely, I did something dumb. I noticed that the Asus ROM for the raid had a lot less options. I think it is newer but what the heck, it works now and I'm happy.
On a side note, windows backup in win 7 works the best of all the windows backups I ever used. I went directly from XP to 7, and earlier I usually used some none MS backup. Shadow copy is nice, why on earth was that dropped in Win 8? But I digress.
Nice to hear that the beta drivers have better performance. I could never find my way around AMD:s site though. What really bothers me is that the information on their own CPU:s on their own site often is wrong or conflicting. Oh well.
Intolerant people ought to drink more beer.