Enabling DVI/DP/HDMI and increasing VRAM with Intel Haswell/4th gen HD4200/4400/4600/etc. iGPU in Graphics Posted September 21, 2018 · Report reply Great debug work, Herve! This can definitely be one thing to try. One question: it's nice that your monitor actually tells you what the problem is! Mine just says "no signal". When the resolution was not correct and the monitor was blank, were you able to find the monitor in SysPref->Display? My problem is that I cannot see this monitor there and I don't know how I can change the resolution (the monitor does show up in IOReg). But you are absolutely correct, my monitors also have different resolutions. Another thing is that I can never get that display panel work correctly since I installed 10.13.6. It never shows the monitor info even if I use built-in HDMI and video works perfectly. All I get is this: No monitor or other options can be found.