i had this same issue with my 5870m when i downgraded to windows 8 from windows 7. my drivers were one version out of date, so i updated them and it didn't help. i then reverted my drivers back 3 or so versions to 12.8 and it works fine now. i dont care too much for using outdated drivers but as long as the clocks are right and i can overclock i'm happy. i haven't tried the new 13.1's yet though.
edit: msi afterburner also had said it wasn't changing the clocks, but catalyst did. it was not changing the clocks though. once i used the older drivers everything would register and afterburner works fine now. not sure if all this is the same as your issue, but it sounds similar. also i dont know what OS you're on. i did not have any issues on any drivers with windows 7. issues only cropped up with 8.