What are the common issues when connecting ultrawide monitors to a MacBook Pro M4

Common Issues

1. Resolution and HiDPI Mode: The M4 MacBook Pro often fails to display the proper resolution options for ultrawide monitors, leading to blurry interfaces and text. Specifically, HiDPI mode, which is crucial for enhancing display sharpness, does not work as expected. This mode typically scales a lower resolution (like 3840 x 1620) to the native resolution of the monitor without losing sharpness, but it is not available on M4 Macs for these monitors[1][2][4].

2. Compatibility with Older Macs: The same ultrawide monitors work perfectly with older Mac models, whether they are Intel-based or use earlier Apple Silicon chips like the M1. However, when connected to an M4 Mac, they do not function as expected[1][2][9].

3. Workarounds: Some users have managed to enable HiDPI mode using third-party apps like BetterDisplay. However, this solution often results in a reduced refresh rate, dropping from 75Hz to 60Hz, which can affect performance and responsiveness[1][4].

4. Cable and Connection Issues: There are reports suggesting that changing the connection method (e.g., from DisplayPort to USB-C) might resolve some issues, although this is not universally effective[1][3].

5. Variability in Monitor Compatibility: Not all ultrawide monitors experience these issues with M4 Macs. Some users have reported successful connections without problems, indicating that the issue may depend on specific monitor models or configurations[10].

Potential Solutions

- Use High-Quality Cables: Ensure that you are using certified HDMI 2.1 or Thunderbolt 4 cables to minimize signal degradation[7].
- Adjust Refresh Rates: Manually set the refresh rate in macOS settings to optimize monitor performance[7].
- Minimize External Interference: Reduce electromagnetic interference from nearby devices to improve signal stability[7].
- Update macOS: Keep your operating system up to date, as future updates might address these compatibility issues[7].

As of now, Apple has not officially acknowledged these issues, but there are indications that they are aware of the problem and may address it in future updates[10].