Very doubtable. Would almost certainly just result in significant portions of dark silicon or such cripplingly low clocks you'd probably be better off with dark silicon. You have more waste heat due to having to have two memory controllers, two banks of memory, external chipset(The APUs are a full SoC), ect that in total would almost certainly lead to at least 20Ws of wasted energy in comparison to an APU based system. And this is besides the fact you'd likely have needed 70W+ minimum from the get go to make proper use of more than one CCX and 11 Vega cores without them throttling.