As long as you have a GPU capable of OpenCL calculations (OpenCL version must be at least 1.2), all you need to do is check your device profiles ("Selected Profiles, click on the corresponding profile to the device you want to work with), select the OPN project, go down to Graphics Card Usage and select yes on all options that apply to your case and scroll down and hit save. Then go to the BOINC Manager and do a manual update.


That should get you GPU work eventually, though be warned that GPU work is quite scarce. Only 2,000 workunits are released every 30 minutes.