My laptop can only support with Driver V9.12.0
The dual graphics HD 7640G + 7470M not working with any version after V9.12.0. It is show screen glitch and scramble sometimes.
In device manager it will show driver HD 7640G + 6800M. I think there is a bug in any driver after V 9.12.0
The latest driver i tried was 13.9 and still not working and show wrong GPU model.