Oh, my mistake! I thought we are talking about a surround system with three monitors? If so it absolutely does make a difference. The H81 will never support SLI or Crossfire, either. So, multi-monitor will hit the wall at two displays. The 770 is capable of four displays, but not on the system described, at least not at anything like what it would do on a PCIe 3.0 MB.
So in the case of multi-monitors the comment about "nor is it even close to being one" is utterly wrong.
Cannot follow the reason-causatility relationship in your sentences. Maybe its my fault.
But 3 full hd monitors can be run easily even on a HD5970. Okay, not the crysis3, but still. And that was many years before this PCIe3.0 hype.
Anyways, if it isnt more expensive, it doesnt hurt to have the newer standard even if its practically useless.
SLI/CF has no real point in it as an upper-mid range card - 770/280x - is able to run anything in full-hd/max setting easily, or on 3 monitors with little compromisses. A real high end card will handle anything for like 4 years, let alone the dual-gpu monsters. Of course, anything is possible, but it only lenghtens your e-peebody just as much as it lightens your wallet.