Downloaded the latest driver for my Radeon HD series 7700 cards (Windows 7, 64 bit), and found out quite quickly that Diablo III failed (Had a bad graphic error message come up). Hearthstone froze into a empty screen of nothingness which also froze the computer. Had to force a computer reboot.
Uninstalled the latest drivers (Revision Number 13.12 Release Date 12/18/2013) and put my older verson on (Revision Number 13.1 Release date 1/17/2013) which fixed the problem and now I can play my games again. The games seemed to have not reconised my graphic cards at all with the new drivers, which made it a real mess.
Could you look into making sure that the 14.3 beta will be compatible with Diablo III and Hearthstone, thanks.