Hey guys. I bought my PC about 2 months ago, i'm running two HD7970's, ones an Asus Matrix and ones an XFX. In the past i have i had both cards slightly overclocked on stock voltages, however, i started getting artifacts and so reset both to default. After a few weeks without any artifacts, i randomly started getting greyish colored artifacts when running World of Warcraft. So i tested both cards individually and seemed to have no issues with either. So i then re-connected the two together. I had no issues to start and my Furmark scores were as normal but after a few hours, they started to come back. Even when i disabled crossfire they remained. I have tried changed the port for the crossfire cables and the same thing is still happening. I have tried re-inserting both cards several times but the same thing continues to happening. I originally thought that it may be an issue that has to do with the crossfire cable, however i'm thinking it could be to do with my processor. Note: I have not touched the settings on either card since the artifacts and they still continue to occur. Any advice would be greatly appreciated. Thanks.