I recently upgraded my system with 2x Radeon Pro Duos(quadfire) and have been able to max out nearly every game at 1440p@144Hz. These cards rock!
However, I'm having some trouble with the Witcher 3. For some reason this game is only using 2 GPU's instead of 4. When looking at MSI Afterburner I see that all 4x GPU's ramp to nearly 90-100% usage, but only two of them are hitting the 1000MHz clock speed. The other two GPU's stay @ 3000MHz and never move. In all of my other games the cards work just fine and all 4x ramp up to 1000Mhz. Although I'm able to achieve 80-100 FPS with everything maxed out, I can't help but think what this game would look like if all 4 GPU's were working.
Has anyone else seen this issue before with quadfire? Maybe the game doesn't support it? Any help would be greatly appreciated!