I made a huge mistake...need help..

[masotime]

I have the exact same Macbook provided for by my company. If you just run it at native 4k without HiDPI scaling, 60Hz will be fine.

More (somewhat confusing) details: I got a cheap Acer B286HK 28″ 4K monitor and it works fine via display port @ 60Hz, 4k. However, I found that screen elements were too small and I generally prefer sharpness over real estate, so I ran it at 1440p HiDPI. This means it is 5k "Retina", which means 5k "retina scaled" to 2k (5120 x 2880 => 2560 x 1440, but each pixel actually using 1.5x number of pixels in reality). This works, and it is sharper, but enormous processing power is required because what OS X does is to render it in internal memory @ 5k, then scale it back.

Wait what what's wrong with the monitor? I currently own a mid 2014 Retina Macbook Pro with the integrated Nvidia 750m GPU, I just ordered the same exact monitor, I thought it was possible to run the full native 4k resolution at 60hz through a mini displayport to Displayport cable?

 

[Nueve]

I have the exact same Macbook provided for by my company. If you just run it at native 4k without HiDPI scaling, 60Hz will be fine.

More (somewhat confusing) details: I got a cheap Acer B286HK 28″ 4K monitor and it works fine via display port @ 60Hz, 4k. However, I found that screen elements were too small and I generally prefer sharpness over real estate, so I ran it at 1440p HiDPI. This means it is 5k "Retina", which means 5k "retina scaled" to 2k (5120 x 2880 => 2560 x 1440, but each pixel actually using 1.5x number of pixels in reality). This works, and it is sharper, but enormous processing power is required because what OS X does is to render it in internal memory @ 5k, then scale it back.

Are you referring to your Acer 4k monitor, or are you talking about the Dell P2715q 4k monitor? If so which one did you like best?

 

[masotime]

The P2715Q is an IPS 4K display, so it is automatically much better than my own Acer 4K which is a TN panel (better color reproduction and viewing angles). I would prefer an IPS monitor myself, but since I use the Acer only in the office (text, mainly) the drawbacks weren't too big of a deal, and it was less than $350 after tax at the time.

I'm pretty sure the Dell monitor will serve you well, just be aware that @ 4k window elements like text and icons may be a bit small. If you run it like I did, at 2560x1440 "retina scaled" then the screen may be slightly laggy, but text will be considerably sharper (not as much as true 5k, but good enough for work).

Are you referring to your Acer 4k monitor, or are you talking about the Dell P2715q 4k monitor? If so which one did you like best?

 

[brand]

boggles my mind that Apple did not launch some kind of adapter allowing the rMB to be used with Thunderbolt.

You do not understand the target market for the new MBA 8,1 or Thunderbolt technology. Do some research on Thunderbolt and you will learn why it is not possible to "launch some kind of adapter allowing the rMB to be used with Thunderbolt".

 

[Sander25]

I do not understand the target market ? Got it.. thanks for your help

 

[Samuelsan2001]

So are you set on 4k60, or would 4k30 be acceptable? It looks like the USB-C to DisplayPort adapter only gets you 30Hz (at least at the moment - I'd be curious to see if that is a driver issue).

If you are committed to 2560@60, you really are going to need a different monitor.

It's a bandwidth issue of the USB C it is only 5Gb/sec in this iteration and 60Hz requires at least 10GB/s (thunderbolt 1) The nest version of USB C will have thunderbolt 3 at 40GB/s bandwidth and should do 5K on a single USB C port. As long as the graphics card is up to it...

 

[ha1o2surfer]

HiDPI large screen - it's better to get a retina iMac for that purpose.

I'm actually doubtful if a rMB can even drive 4k @ 60Hz properly. I'd stick with a rMBP if I wanted to do that, preferably the 15" with dedicated graphics. Note that running 1440p HiDPI on a 4k monitor is actually more difficult than running it at native 4k since it is 5k down scaled to 4k.

Definitely ditch the 4k monitor and go with a standard 1440p monitor, preferably with HDMI inputs for less grief in general.

HiDPI and monitor bandwidth are not related.