I use a Lenovo Z51 (Intel integrated graphics) with AMD discrete R9 M375 and am able to use GPU PerfStudio.
You will need to use the Radeon settings to control which GPU is used for each application. Open Radeon Settings, go to Preferences, click on Radeon Additional Settings. This will open the Radeon Additional Settings UI. Click on Switchable Graphics Application Settings, select your application and set the Graphics Setting to be "High Performance".