PCIe 2.0 Bottleneck

Solution
It wasn't clear in your post whether you intend to run 2 cards or 3. If 2, your motherboard can do dual x16 (PCI-E 2.0). If 3, then yes, one of them will run at 8x (PCI-E 2.0), but then again, 3-way crossfire is hardly worth it, just another reason not to do it.
It wasn't clear in your post whether you intend to run 2 cards or 3. If 2, your motherboard can do dual x16 (PCI-E 2.0). If 3, then yes, one of them will run at 8x (PCI-E 2.0), but then again, 3-way crossfire is hardly worth it, just another reason not to do it.
 
Solution