>>51056364increasing the resolution is more like a " trend " than anything what really matters. you can play diablo 2 in 4k surround , but it won't actually look any better than on 720p. resolution itself won't make any game look better.
Increasing the resolution has a huge effect on the detail of objects in the distance. but of course if you play on medium, then the distannce scaling is too low to make any effect, because the distanced objects are not rendered in high enough quality to take advantage of 4k /1440p res, so it's kinda pointless.
My personal opinion is pretty simple. The best gameplay experience can be achieved on a stable 60 fps with ultra or maxed out graphical settings on 1080p.
This is achievable in most games with a single gtx 980.
I will only move to higher resolutions when gpus will be capable of achieving a stable 60+ fps on maxed settings on a SINGLE GPU card. I guess this will happen when the new nvidia flagship pascal architecture card hits the market in 1 year or so.
conclusion:
aim for 1080p ultra max detail, that will be the best experience both graphically and gameplay wise.