im a relative n00b here so please be gentle I am quite techy though, so hopefully not embarrassing myself too much! I have a 2014 13" macbook pro, which i adore. Esp the retina display. BUT the screen real-estate is starting to hinder me for my work (im a network engineer, having many apps open at once is key). So, consequently, I have been looking into external display options. The Samsung U28E590D is a frontrunner (3840x2160 "4K ultra HD"). However i have some questions before i purchase that no amount of reading seems to allow me to de-tangle, and in fact, i seem to be confusing myself the deeper i go! so here are my questions, any and all help is appreciated from the guru's on this forum: QUESTIONS: 1/ my MBP graphics card supports (from the apple marketing specs) "up to 2560 by 1600 pixels on up to two external displays".... the new samsung has more pixels that this [3840x2160], and not in a "nice", ie. 2x multiple of either, so what happens here? Scaling I guess. Is this handled by the monitor? or the MBP OS? will i notice blurry text etc as a result? Clean, crisp lines / text are important to me. Will the scaling introduce noticeable lag? 2/ How to feed this monitor: HDMI vs displayport? The monitor supports both, but from what i can gather HDMI output from my MBP only allows "Support for 1080p resolution at up to 60Hz", which is well short of what my GPU can drive [2560x1600]. So i guess this scrubs HDMI? I do see that if i bump down to 30Hz it supports for 3840x2160 (the exact samsung res!) but do i want to go there? what does halving the refresh rate do to usability on modern monitors? im mostly about application productivity, not gaming etc... 3/ Assuming we scrub HDMI, it leaves displayport. It seems my MBP has 2x thunderbolt-v2, which supports displayport-v1.2 (~18Gbps, the standard designed to support 4K monitors @60fps)... so this would appear to be a good thing, BUT looking here (https://support.apple.com/en-au/HT204149) it seems if i get the single-port-to-DVI-adapter it supports only 1920x1200. The dual-link version allows me to go over this (upto what is unclear)... should i be purchasing this dual-link adapter? I guess so, to be able to push the maximum out of my GPU, but this then circles back to my question-1, i.e. will the resolution mismatch make things look crap. 4/ somewhat bizarrely, the Samsung U28E590D doesn't have a DVI input. This means i guess i have to do something like this: MONITOR[displayport]<-> DISPLAYPORT-TO-DVI-ADAPTER/CABLE <-> DUAL-LINK-APPLE-ADAPTER <-> MBP I assume there is no pitfalls associated with this? please don't tell me there is another resolution calculation to make because of this! 5/parallels is *sometimes* noticeably laggy (ie 1 second click / refresh delay!) when i run an external monitor. Most of my work apps are run out this VM unfortunately. Ive yet to get to the bottom of this. OSX appears to be fine, just the VM suffers. Is this problem likely to get worse on a higher res display? I guess all this boils down to is: will i be happy purchasing this new display, or will the fact that its such a high res actually be a step backward with all the above pitfalls (or alternatively, am i looking far to deep into this!!!). thanks in advance guys K.