Fixing HDMI Issue on Skylake ThinkPad E450 Running macOS Monterey

Guide:

If you're experiencing issues with HDMI output on your Lenovo ThinkPad E450 running macOS Monterey, follow these steps to troubleshoot and resolve the problem:

1. Check HDMI Cable and Connection:

• Ensure that the HDMI cable is securely connected to both your ThinkPad E450 and the external display.
• Try using a different HDMI cable to rule out any potential cable issues.

2. Verify Graphics Configuration:

• Check your EFI configuration and make sure that the necessary graphics patches and configurations are applied for Skylake notebooks.
• Ensure that you're using the correct framebuffer patch for your Intel HD Graphics 520 GPU in your config.plist file.

3. Verify macOS Monterey Installation:

• Confirm that macOS Monterey is installed correctly on your ThinkPad E450 and that there are no issues with the installation.
• Check system information to ensure that macOS recognizes your GPU and HDMI port.

4. Reset NVRAM and SMC:

• Reset the NVRAM and SMC on your ThinkPad E450 to reset various system settings that could affect HDMI output.
• To reset NVRAM, restart your Mac and immediately press and hold Command (⌘) + Option (⌥) + P + R until you hear the startup sound twice.
• To reset the SMC, shut down your Mac, then press and hold the Shift (⇧) + Control (⌃) + Option (⌥) + Power buttons simultaneously for about 10 seconds.

5. Test HDMI Output with Different Displays:

• Connect your ThinkPad E450 to different HDMI displays to see if the issue persists across multiple displays.
• This will help determine if the problem lies with the ThinkPad E450 or the external display.

6. Verify BIOS Settings:

• Check your ThinkPad E450 BIOS settings and ensure that there are no settings related to graphics or display output that could be affecting HDMI functionality.
• Update your BIOS to the latest version if available.

7. Try Different HDMI Port:

• If your ThinkPad E450 has multiple HDMI ports, try using a different HDMI port to see if the issue is specific to one port.

8. Check for macOS Updates:

• Ensure that your macOS Monterey installation is up to date by checking for any available updates in System Preferences > Software Update.

9. Consult Hackintosh Community:

• If the issue persists after trying the above steps, reach out to the Hackintosh community forums or Reddit for further assistance and troubleshooting tips specific to your hardware configuration.

By following these steps, you should be able to troubleshoot and resolve the HDMI issue on your Skylake ThinkPad E450 running macOS Monterey.