I read somewhere that this can be done has anyone tried this at all and if so any issues?I already have a powercolor pcs r290 and was thinking since theres only like a $5 difference in price between the powercolor 290x and the 390 i would go for the 390 and use it as my top card then when i need the little extra power at 1440p enabling the 290 along with it.I realize that the vram will be reduced to 4gb with both cards enabled but i dont see a benifit at this point from 4gb to 8gb at 1440p anyways.thoughts?