Crossfire scaling not working properly
I have 2 AMD Radeon HD 7870s crossfired, but instead of having a boost in performance compared to a single HD 7870, performance is actually decreased when crossfire is enabled. I've tested it out on both Bioshock Infinite and Battlefield 3, but both show a drop in performance compared to a single 7870. The Heaven benchmarking utility actually shows an increase in performance though. My friend and I have tried various fixes, but none have worked so far. My specs are:
OS: Win 8.1
CPU: AMD FX-6300
Mobo: MSI 970A-G46
GPU: (2) ATI AMD Radeon HD 7870
PSU: Rosewill 750w 80 plus bronze