While playing games i'm getting black rectangular artifact patterns all over my screen. This artifacting problem started after updating driver for my AMD Radeon HD 7950. When i alt+tab desktop works perfect. Also Gpu's fans spinning much faster than before and It's heating a lot. I had this heating problem last month too but after upgrading the driver it was solved.
I'm using WIN10 as OS. I attached a screen shot of it.
increase the core voltage using MSI Afterburner. Your card is not getting enough energy.