Hmm, my ATI6850 has served me well and continues to be viable for working my way though my Steam back catalogue, but... but.. I've had more than my money's worth and I'm due an upgrade, or something
980 or 970? 970 at a glance appears a lot better value and an amount I'm comfortable throwing down (its $450 v ~$770 here in UK). That said a faster card can be more enjoyable for a longer time so can, like expensive shoes, be argued better value over the long term (in some respects). I'd be pairing it with a 2500K at 4.2ghz, also aged but cpus don't seem to have come on much.
I think I'm leaning towards the 970.
Hmm I might have to check my PSU power connectors, current card only required a single 6 pin.
Oh and crap, how is it these days for swapping cards whithout doing an OS reinstall? That would be really quite a nuisance.