Does Retina display affect gaming performance because of a higher resolution screen?

I use my MacBook Pro 13" Early 2015 for development and such, it performs well (I'm assuming Intel Iris 6100 is more than enough to handle these tasks at the retina display's resolution). I do enjoy some gaming here and there. So I was wondering if the increased amount of pixels in the display are taxing the system even if games are being ran at lower resolution (maybe 1280x800 full screen)? Would there be less work on the CPU if I had a non-retina display?

I had a Mac Mini Late 2014 which had an Intel Iris 5100 and played on a 1080p monitor. I installed a game I played on the Mac Mini (FFXIV) on my MacBook and it feels as though the MacBook performs equally or slightly worse. I may just be imagining things or analyzing too closely with criticism. Any comments or explanations on this matter would be greatly appreciated!