Limitations of Macbook Air 2013 + RX 580 + Powercolor Gaming Station
Hey folks! I'm trying to figure out what I should expect as the maximum resolution and refresh rate for my setup as I was hoping for better than what I'm achieving.
TLDR; I want to be able to get 5120x1440p @ 30Hz, but Mac OS X only gives me a max option of 3840x1080p @ 60 Hz.
Macbook Air mid-2013
- Running Mac OS X Catalina 10.15.3
- i5-4250U 1.30GHz CPU
- Intel HD 5000 Graphics
- 8 GB of ram
- Thunderbolt 1 port (so 10 GBps)
- Using an XFX RX 580 that has three displayport and 1 HDMI output
- Currently the HDMI is hooked up to my monitor
- Leveraging one USB port tied to a cheap USB kvm so I can swap between my work and personal laptops
- Using the Apple Thunderbolt 2 <-> Thunderbolt 3 adapter + the Apple Thunderbolt 1/2 cable to connect to my Macbook Air 2013
Samsung C49RG90 49" Monitor
- Above eGPU connected via HDMI is currently driving at 3840x1080p at 60Hz
- Separately, using Caldigit TS3 Plus with work laptop (from 2019) to drive at 5120x1440p at 60Hz
What I want
My hope was that I would be able to squeak out 5120x1440p at 30Hz from my eGPU setup. Presently, connecting the Macbook defaults to 2560x720p at 60Hz and I have to open the display settings, Alt+Click on Scaled, and select 3840x1080p at 60Hz.
With 3840x1080p, the text is a bit blurry and giving me a little bit of a headache. I've fiddled with adjusting the sharpness a bit on the monitor, but was hoping I could get the desired resolution.
I've seen a couple of other posts of folks with the same Macbook, using an RX 580 (or other AMD GPU) and driving a 4K monitor. My hope was that I could achieve the 1440p output given I keep hearing that the 5120x1440p output is less demanding than a true 4K monitor.
Is this possible to do? Should I be trying to figure out a solution or is my Macbook Air too limited with a thunderbolt 3 port to be able to drive the resolution I want?
I tried out the 10 day trial of SwitchResX and it was able to list and apply 5120x1440p at 60Hz, although without HiDPI available. Not sure if I trust the 60Hz right now, but it does appear to be running in 5120x1440p, so well worth the full payment from me.
@senkwich, Isn't 2560 x 720 a HiDPI mode? All those resolutions listed in your screen shot that don't say "(low resolution)" are HiDPI modes.
In SwithResX, the Display Information tab should show that the Scaled Resolution Base is 5120 x 1440.
For all the scaled resolutions, you should be able to double click them in the Current Resolutions tab to show the timing information. Active should be 5120 x 1440. For HiDPI modes, the Scale to numbers should be twice as wide and tall as the HiDPI width and height.
@joevt, yeah, you're right in that the 2560x720 is HiDPI mode. I was trying to get the full resolution of 5120x1440 (without HiDPI) and Mac OS X wouldn't let me select it.
I wasn't sure if there was some limitation as I figured that being able to drive 2560x720 @ 60Hz with HiDPI was saying that it could handle the full resolution fine.