I'm having the same issue. The 3 cards were working fine when I had a monitor hooked up via HDMI cable inside my office. Now I had to move the rig outside my house b/c the A/C was competing with the heat and working nonstop so all I did was to install a wifi card and took the rig to my storage unit behind my house. Now I don't have a monitor to plug into it but I created 3 dummy plugs and still doesn't fix the issue with the 3rd card running half the speed. Without the dummy plug, I wouldn't even get the temperature to show up so that fixed that but why can't the 3rd card run full speed?

I see this thread has been here for a while, were you ever able to start accepting bitcoins on eBay?