[Help]AsRock Z75 Pro 3 & Triple Xfire

Hi guys, this will be my first post on these boards and I'm in need of a little bit of help. I've come here before for help and found solutions, so hopefully I can find this last one to feel comfortable with my build.  

I'm not new to computers and I've built a few before, but I'm not big into multi-GPU based builds and now I'm wanting to get into the gaming scene for the upcoming titles and try out this scene. I've already compiled a list of parts that I'm going to be building my new gaming PC with, but I need a little bit of help understanding one aspect on the motherboard I've chosen.

For the record, I've already got most of the parts, and they are as follows:

Intel Core i5 2500k
AsRock Z75 Pro 3 <------ Need a little information on this board.
Hyper 212 Evo
16Gb Corsair Vengeance
2x WD Black 1Tb
Force GT 120Gb
2x XFX 6850 1Gb <--- Ordering another soon (If I get my question about Tri-Xfire answered here)
600T White Edition
Corsair 750 TX

Now, the reason I'm seeking help is about the motherboard. I've checked out AsRock's site about this board and it has it listed to be able to run both CrossfireX and Quad-CrossfireX, but I'm stuck wondering if this board will run three 6850's in Xfire? I'm under the assumption that by Quad-CrossfireX, it means that it can handle TWO dual GPU based units (like a 6990?), instead of THREE single GPU units, such as the 6850's. Yes, I know, you're probably thinking three 6850's is either outdated or not worth the money, but keep in mind, I got my first two GPU's completely free and I'd like to buy my third if I'm able to run it with this board. Now, the board itself has only 3 PCI-E lanes, so I'm kind of stumped.

Any help would be greatly appreciated. Also, here's a link to the motherboard if you need it:

http://www.asrock.com/mb/Intel/Z75%20Pro3/

Thank you.