2019 MBA performance running a 4K monitor (like 2560 x 1440)

[CrispyUK]

Hi,

Currently looking at the 2019 MacBook Air for productivity purposes, primarily Microsoft Office, web-based apps and video calls. Want a USB-C monitor with power delivery for a tidy single cable connection when using at my desk but struggling on the decision between a 1440p and 4K for a 27" screen.

Ideally would like something visually close to the 27" Retina 5K iMac, which suggests going down the 4K route and scaling it to look like 2560 x 1400 to give equivalent desktop real estate.

But...I'm hesitating because I don't know how well the MBA will perform running a 4K display with non-integer scaling - anyone doing this already that can share their experiences? Does everything run smoothly or do you get lag/jittering on animations, etc.? The 'default/best for display' 2x scaling (like 1920 x 1080p) makes UI elements too big on a 27" screen.

My closest experience is a 2017 MacBook Air running a LG UltraFine 5K display at scaled resolution and this felt sluggish and caused the fan to run most of the time, so makes me wary!

 

[mouthster]

I hooked up my wife's 2019 Air to my 4k monitor and tried the different scaling modes, it's pretty choppy. The real test is clicking the Launchpad icon in the dock. It takes a bit to even start the animation, and it's choppy when it starts. It actually performs worse than my 2014 MacBook Pro with integrated Intel Iris Pro graphics. My work issued 2019 i9 Pro with Radeon 560x is smooth as butter.

I love the form factor of the Air but I like smooth graphics, so I'm holding out for the 16" MacBook Pro as integrated graphics aren't enough for 60fps stutter-free animations on 4k screens with HiDPI scaling.

 

[auxbuss]

I don't have a 4k, but I use a Dell U2715H (27") in its native 2560x1440 without difficulties on a base model MBA. (The monitor is a few years old, so I use £10 DP to USB-C converter with it.)

 

[Cehape]

I hooked up my wife's 2019 Air to my 4k monitor and tried the different scaling modes, it's pretty choppy.

How is the performance in looks like 1920x1080 resolution? That should be ok. I‘m asking, because I plan to buy the 24 inch UltraFine.

 

[mouthster]

How is the performance in looks like 1920x1080 resolution? That should be ok. I‘m asking, because I plan to buy the 24 inch UltraFine.

It's pretty good. 1440 and above is where I start to see hitches.

 

[Cehape]

Thank you for trying and replying

 

[CrispyUK]

Thanks all, appreciate the responses. Looks like I might be best with a decent 2560x1440 USB-C monitor!

 

[alexandero]

I'm running a late-2016 13" non-TB MBP with a Dell P2415Q (3840x2160, so a 1920x1080 UI in retina-resolution) without problems. I would assume that any choppiness with a new MBA is related to a connection with 30Hz instead of 60Hz – so I suggest to ensure you connect it properly, e.g. when using a USB-C dock check if it supports a 4K/60Hz screen (Caldigit does, when installing a special firmware provided by Caldigit on request).

 

[Jimmy James]

It baffles me that a modern, not inexpensive computer, can struggle with basic tasks on what has become a fairly standard resolution.

 

[mouthster]

I'm running a late-2016 13" non-TB MBP with a Dell P2415Q (3840x2160, so a 1920x1080 UI in retina-resolution) without problems. I would assume that any choppiness with a new MBA is related to a connection with 30Hz instead of 60Hz – so I suggest to ensure you connect it properly, e.g. when using a USB-C dock check if it supports a 4K/60Hz screen (Caldigit does, when installing a special firmware provided by Caldigit on request).

I was running in 60hz. 1920x1080 works well because its /2 of 3840x2160 and super-sampling doesn't occur. If you use "Looks like" 2560x1440 the desktop is actually being rendered at 5,120x2,880 and then super-sampled back down to your screens resolution (4k). This is taxing for integrated graphics where the maximum amount of system RAM available to it is 1.5gb.

 

[AlexJoda]

It doesn’t make sense to scale down a 4K monitor to anything different than half its original resolution because you get a blurry picture that is worse than an unscaled non 4K display. That would result in 1080*1920 which is a very low resolution for an 27“ display. In that case a native 1440p display is the better choice and the MBA has no problem with that...

I use a good 1440p IPS display together with my 5K iMac and the difference is not „night and day“. I can live well with it as a second display. The only (expensive and demanding) alternative to 1440p is a real 5K display....