so your using the 10.9 drivers? and your sure they installed properly? and also if you havent tried it turn all the monitors to 800x600 before trying to enable eyefinity.
disable 2 of the 3 monitors, and then try to create group. also you could try rotating the connectors. basically try each monitor plugged into a different connection port. i would try the 1280x1024 with the DP adapter first.
when you try to create a group does it just not display all connections? before when your at the "Desktop and Displays" tab does it show all 3 monitors on the bottom of the page?
I had that problem a lot trying to get my eyefinity set up.
When you pull up CCC and the eyefinity display group UI, does it happen to say that one of the monitors is disabled? If you rightclick on your desktop and go to display properties, it should detect multiple monitors in the dropdown. Is one of the options in the dropdown disabled?
If so, I had to repeatedly (I mean repeatedly) click 'detect' on the UI until it acknowledged the montiors were connected. And then even then it was onlys howing the monitor plugged into the DP as a 'non plug and play montor' that only offered 640x480 res. I do forget the actual details about what I had to do to get it right, but it started with getting all 3 monitors on, then all 3 monitors set to 1280x1024 (my case) resolutions, and then i could set up an eyefinity group.
In fact, I just updated to 10.12 and after my most recent windows update, the machine came back on with 2/3 monitors on (the DP monitor was not on). I'm hoping I'll just need to do a cold reboot. I've found that sometimes if you do a 'soft' reset on the machine, the monitors do not come back in the correct eyefinity configuration.
Thanks to all those who responded. Turns out PowerColor has an unpublished bios update for this. I called support and got the bios update for the video card and everything works -- I have three screens powered by the same card. Awesome. I don't even need the ATI software installed to achieve this.