Don't know why asrock mobo tend to have this problem. Saw quite alot of bros having this problem recently. My asrock b75 pro 3 m have the exact same problem as yours, fan spin then off, then fan spin again then off repeatedly. Tried reseat ram and the problem was fix but after few months later mobo die completely reseat ram also no use.
Think you should just buy a new mobo and replace it yourself or ask the local distro to do for you ba. Then when the rma board comes back can just sell it or keep as back up. Better then waiting until nov then can use computer.