Actually I didn't discover it myself. I found the solution at one Russian forum, so I don't know why it works and how it has been discovered :crazy: . I can't give the link because once I put a link in a message the message doesn't appear (I've tried a couple of times).
Hi, I've managed to get it worked.
The problem is in the new AMDRadeonX4000.kext.
The new values in 10.10.3 for "cail_properties" of AMDVerdeGraphicsAccelerator driver are: