Hi,
I had the same problem. I managed to solve it by your way. Also later, I noticed a switch in Ati Tray Tools v1.7.9.1557.
Go to Game Profiles / Manage Profiles / Direct3D Tweaks. Set "Force VSync (Vista workaround)" to "ON".
This also worked for me.. You may ditch RadeonPro if you like now...
Cheers...