Hi Guys, I am using a late 2013 macbook pro with a new external dell monitor U2414H. I am having similar problems to others whereby the text and fonts on my external display are pixelated quite badly, this is not in relation to going from a retina screen to a non-retina screen as I have other systems with 24 inch monitors that don't look like this. There is clearly a problem. I have gone through various diagnosis based on things i've come across online. I have: Used different leads HDMI, Mini Display, Mini Display -> HDMI Reset RGB (forced override with Ruby script) Adjusted sharpness and colour with monitors physical display settings I don't know what else I can do to get this working or where exactly the problem is coming from. Is it an issue with the rMBP or my Dell monitor. If it is the latter I will return the Dell and purchase another monitor, however if its a known issue with the rMBP I will have to just come to terms with the fact that my 2000+ pound computer cannot run an external display . Appreciate your input, thanks!