Will Asus P8H77-M use msi 7850 crossfire?

[Corsario]

Hi, I have a P8H77-M motherboard, and a msi 7850 twinfrozrIII, and I would like to crossfire with an equal 7850. A friend of mine told me that the second graphic card will not run at its capacity because this motherboard only has one 3.0 pci express slot, and the slot where the second graphic card will be connected will cut the speed in half of it´s possibilites. I would like to know if he is right, and it´s no use in crossfire this GPU with this motherboard.

This is my motherboard http://www.asus.com/Motherboards/P8H77M/

Multi-GPU Support
Supports AMD Quad-GPU CrossFireX™ Technology
Supports LucidLogix® Virtu™ MVP Technology *1
Expansion Slots
1 x PCIe 3.0/2.0 x16 (blue) *2
1 x PCIe 2.0 x16 (x4 mode, black)
1 x PCIe 2.0 x1
1 x PCI

 

[iTek]

Hes right in a sense but the performance won't be drastically reduced.

 

[Corsario]

Would you advise me to get other motherboard to get the best performance out of the other GPU or the improvement isn´t that significant that would justify such an upgrade of the motherboard? If so, what motherboard would you recomend? Can´t be too expensive, but that would do the job of crossfiring properly.