As you already know, there are Crossfire 6670HD. I heard when you crossfire both they act like a 7770HD. If you triple fire with the APU's, they could top a single 7800's card. I'm sure it will be the same in price but less in power consumption.
Please answer my question. Can you triple fire with 2x 6670HD cards and the AMD A10-5800K APU. Like combine all 3 for 1 game?