My Dell XPS 8920 has dual system windows 10 and ubuntu. Now it can only turn on Ubuntu when I plug in the HDMI cable in the upper display portal. If I turn on the PC and press F12(that's how I turn on windows mode), the monitor has no signal.

By the way, everything was fine until yesterday I left my PC on sleep mode. And it never wakes up.

I have tried disconnect and replug all the cabel and power supply. It does not work.