Issue is resolved: I used a MiniDP ver1.2a cable to Display Port instead adapter. It might be that the MiniDP adapter to HDMI does not support 1.2 version of DisplayPort. Working in clamshell mode is also works after switching the cable.
I'm not sure what I've missed, my patched MacBook Air only works 2560 x 1440 (low resolution) and 1280 x 720. Other than that, the monitor will shown as black screen (power saving indicator turned on). Strangely, the MacBook still detects the monitor (not as turned off). I want to accomplish 2560 x1440 (high resolution), because my other MBP and the monitor is confirmed to support the resolution.
Additional issue: I'm unable to work with clamshell mode (with MagSafe on). Previously I was able to work in clamshell mode before patching.
I believe in this article that MacBook Air 2015 is capable to support 60hz 4k external displays.
Monitor: Lenovo ThinkVision T27p-10 (4K Monitor)
Device: MacBook Air early 2015 (macOS Mojave 10.14.6)
GPU: Intel HD Graphics 6000 1536 MB graphics
Connected with MiniDP adapter to HDMI
works with DDC-CI - MonitorControl (GitHub)
Issue is resolved: I used a MiniDP ver1.2a cable to Display Port instead adapter. It might be that the MiniDP adapter to HDMI does not support 1.2 version of DisplayPort. Working in clamshell mode is also works after switching the cable.
I'm not sure what I've missed, my patched MacBook Air only works 2560 x 1440 (low resolution) and 1280 x 720. Other than that, the monitor will shown as black screen (power saving indicator turned on). Strangely, the MacBook still detects the monitor (not as turned off). I want to accomplish 2560 x1440 (high resolution), because my other MBP and the monitor is confirmed to support the resolution.
Additional issue: I'm unable to work with clamshell mode (with MagSafe on). Previously I was able to work in clamshell mode before patching.
I believe in this article that MacBook Air 2015 is capable to support 60hz 4k external displays.
Monitor: Lenovo ThinkVision T27p-10 (4K Monitor) Device: MacBook Air early 2015 (macOS Mojave 10.14.6) GPU: Intel HD Graphics 6000 1536 MB graphics Connected with MiniDP adapter to HDMI works with DDC-CI - MonitorControl (GitHub)