I bought LG 23MP67HQ as my second monitor because it has HDMI input.
Tested OK and well at the shop.
It has two display input, VGA and HDMI.
My first monitor has VGA and DVI port.
My graphics card is ASUS STRIX GTX960. Which has three display ports, One HDMI and one DVI.

The problem is windows couldn't detect the correct EDID thus using non-native display (1024x768) when connected using HDMI. Correct EDID were detected only when using display with VGA connector.

So, I begin troubleshooting.
  1. Changing the HDMI cable ... same problem.
  2. Connecting using my laptop (MacBook Air) ... same problem (and flickers).
  3. Checking my laptop and PC by connecting it to the TV using HDMI ... no problem, works fine.
  4. Connecting to the monitor using HDMI as the only monitor to my PC ... same problem.
  5. Connecting to the monitor using VGA as the only monitor to my PC ... no problem, works fine.
  6. Connecting to the monitor using VGA as the second monitor to my laptop... no problem, works fine.
  7. Go to the shop and tested the display using HDMI ... no problem, works fine. (WTF)


So, what is the problem?