Does anyone have a rMBPro13" 2015 with a dell up2414q 4k? Does it lag at 60hz via display port? I know it is supposed to work but my question us about fluidity and performance.. Does the display jitter and lag? Does the Macbook have to work so hard that other tasks suffer? Does it heat up and spin fans up? This is the adobeRGB monitor not the p2415 that everyone is taking about at the moment.