for linux i need NVidia ... ?
maybe its time to get upgraded

and yes. i tried beta.. had some WU with very low credit
It can be risky from point of view, sometimes WU fail or deliver less points during beta testing and you wouldn't receive any help in the main support forum if not member of beta tester group.
Better set client type on advanced.
Oh, and linux as OS with client v7 also don't get any core 15 or 16 ;-)