Even as dual socket AM3+, it would be faster than i5 4690k not by much. From looking at mersenne.org's cpu comparison of iteration times, it looks like 2 amd 8 core processors would do about 1/4 more work than i5 4690k in the same amount of time. At a cost of more electricity. I'd still be interested if a dual mobo existed. Or better, dual lga-1150 socket.