Downloaded Catalyst 13.1, tried all the settings in the thread again it never goes above 700 ... 
Did you also try Catalyst 13.4? (Or was it what you were having trouble with earlier?)
Yesterday I tried catalyst 13.4 and today 13.1, seems strange because some guy told me he has the same cards :S...
Which OS do you use?
If I were you, I would try Linux (a clean install) just to eliminate other possible causes of the problem.