HDMI no signal debian

Question

I'm using a lenovo ideapad 320s. I can see that HDMI1 is connected in xrandr but no picture. Is it possible that the hardware is too new? and should I just move to debian testing to see if that works? In xfce4 gui display application I can see that my HDMI display is disabled but can't see how to enable it. Also "xrandr --output HDMI1 --auto" doesnt help.

Code:

OS: Debian 9.1 stretch  
Kernel: x86_64 Linux 4.9.0-3-amd64  
Uptime: 8m  
Packages: 1789  
Shell: zsh 5.3.1  
Resolution: 1920x1080  
WM: i3  
GTK Theme: Arc-Dark [GTK2/3]  
Icon Theme: Tango  
Font: Sans 10  
CPU: Intel Core i5-7200U CPU @ 3.1GHz  
GPU: Mesa DRI Intel(R) HD Graphics 620 (Kabylake GT2) 

Answer 1

1. unplug hdmi
2. power cycle computer
3. power cycle computer again
4. plug in hdmi

mine worked after the second cycle. But never after only a single cycle.