Hi,
I have exactly the same issue and have investigated extensively to find a solution. I have 2 miners with the following set-up;
1/ AsRock H81 Pro BTC (BIOS version 1.5) with 5x Sapphire R9 280X Toxic running on Windows 8.1
- AMD Catalyst driver 14.6 installed
- sgminer 4.?.? MODB2 (will try...