Mac Mini 2014 doesn't support VGA / DVI

[fred_Mpro]

Hi,

I have a big problem with my Mac Mini 2014. When I connect an HDMI screen everything works. When I connect a screen equipped with a DVI or VGA connection with the Apple adapter have no image in the Thunderbolt A (closer to the power) and when I connect it in the thunderbolt B (closer USB) have a low resolution image. The image disappears before the desktop opens. The Mac seems to work but no video.

Interestingly, when I use the Thunderbolt port with a mini-display adapter to HDMI ... surprise everything works in both ports ..

I try several things:
- Reinstall the system : No
- 4 different screen...hdmi, vga, dvi-i DVi-D Single Link...
- 3 adapter... Belkin, Apple, china crap
- Try to open with external OSX : Same problem
- Try to fresh 10.13 installation for Firmware update : No
- Go to the apple store... new logic board... : SAME
- wtf...

Has anyone ever had a similar problem? I do not understand what the problem is ... It's not software.

This is the device of a subcontractor ... I can not just say to him: Buy yourself an HDMI screen ...

Thanks,