Interesting question. Got one idea to throw here. This is my own conclusion based on data available. Know why PCI-E version and # of lanes affects configurations with multiple (Nvidia) graphics cards on multiple high resolution monitors? It's because Nvidia is already using PCI-Express to transmit data (frames and split frames) between cards. The question is this: why would we need higher bandwidth than one or two cards would need if we're simply using more cards? Isn't data equally transmitted and VRAM mirrored across all cards? Isn't it the only obvious difference that the CPU is simply pushing more FPS now? From that data we can extrapolate PCI-E bandwidth requirements for bridgeless CrossFire at the extreme end of the scale. On a single monitor AND / OR one or two cards, the bandwidth requirements would likely be a bit higher than bridged CF. All in all, with increasing resolutions, refresh rates, and number of monitors, passing data over the bus that is not very populated anyways (PCI-E) is the smartest decision, and I bet that Nvidia will be into bridgeless SLi soon as well. Let's face it, that bridge is useless if you're using it for single monitors (or low requirements in general) since that has a minimal bandwidth requirement relative to what PCI-Express offers.