Normally I would suggest that too, but considering OP's mentioned that he would need it to be as quiet as possible for his future migration to mini-itx, it would be better to consider a lower-power consumption card such as the 270s.
Beg pardon, I meant "micro ATX" but typed "mini ATX" thus confusing the issue completely. In my head, I'll be keeping my current 600W power supply, so power draw per se isn't an issue. The big question is space and noise - if there's a 250 watt, quiet option that will fit, then I'll certainly consider it
270X was really just what I figured was most sensible given my budget (sub-£200 ideally) and a vague desire to support Mantle.
Even at 28 I'd have to get a longer SATA cable. Current card is a modest 26.
Maxing modded Skyrim would be nice, but it's not an everyday game so I could live with slightly less detail. Either card will walk Wildstar Online I'm quite sure 