I have a laptop with 2 GPUs. ATI Mobility Radeon HD 5650 and Intel HD Graphics. About this Computer say under Graphics: Intel® Ironlake Mobile
I tried using the proprietary driver under System Settings -> Software&Updates -> Additional Drivers: from fglrx.
After a restart the System crashed it startet in low graphic mode The XServer gave me a fatal error.
Is there a way to install the Catalyst program under Ubuntu 15.10? And how? I did not find out.