Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

andy9l

macrumors 68000
Original poster
Aug 31, 2009
1,699
365
England, UK
I'm changing my setup away from an old iMac with Bootcamp to a purpose built gaming PC and my MacBook (12", Early 2015) that will both use the same screen. I'm keen to grab a 4K screen, since they are the way forward as HiDPI support continues to improve.

I know my MacBook only supports 4K @ 30Hz, and that's fine - I'll be switching to a MacBook Pro in due course anyway.

The screen I'm looking at is the 27" Dell P2715Q, which has a native resolution of 3840x2160.

Questions:

1. Ideally I want to use the monitor scaled to "look like" 2560x1440 via my MacBook (30Hz is fine). Or something around that, at least. Is this possible?

2. If it's not possible on a 2015 MacBook, is it possible on a 2016 MacBook Pro?

3. Anyone else using a 4K monitor with their MacBook (preferably 2015 model) that does allow for scaling?
 

BeatCrazy

macrumors 603
Jul 20, 2011
5,138
4,516
Good news, the 2015 MacBook supports 4K at 60Hz via DisplayPort. No hack required, only macOS Sierra. Confirmation here.

You'll need something to covert the USB-C to DisplayPort Alt Mode, I use the CalDigit USB-C dock @ $150. The only downside is USB speeds reduced to 2.0. But it looks great!
 

andy9l

macrumors 68000
Original poster
Aug 31, 2009
1,699
365
England, UK
Thanks for the reply - that got me researching further down the DP/USB-C route.

Ended up buying an LG 27UD88-W monitor (~£400-500) for the USB-C connection after seeing excellent reviews on YouTube etc.. It does 4K @ 60Hz via HDMI 2.0, DP, and USB-C. Covers all bases for my gaming PC and MacBook / future MacBook Pro.

I'll have to deal with 4K native, or 1080p @2x ("retina") on macOS for a while until I get a MacBook Pro that can do the proper macOS scaling for "looks like 2560x1440". My understanding is that the rMB cannot handle that type of scaling on HiDPI external monitors - it would probably melt.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.