HP X360 1040 G5 Black Screen with activated Thunderbolt

[Katja_bo]

Hello,

i have a troubel with starting my Notebook with activated Thunderbold.

if i have activate Thunderbolt in Bios, the Notebook wan't start. I can't see the Startuplogo, the Screen is Black. 

The Backlight of my Keyboard is on for a while, the amber Light on F11 goes on for a while, like a normal startprocess.

But thats all, the screen remains black.

The back light of the screen does not start.

The only way to get back into the BIOS is to open the backside of the notebook, disconnect the battery, wait a little bit, re-connect the battery and start it.

The first time you start, the message "Performance drop" is received.

With luck I get the Bios Startscreen at the second start, If not, battery off, wait, clamp again.

That's until I get the Bios Startscreen.

I don't understand why but after a few attempts the start works until the Bios Start.

If I then deactivate Thunderbolt, the computer will start again normaly.

But: Via USB C i cant get an external screen connected and HDMI is no longer possible.

The behavior is completely new for the computer. It has emerged from one day to the next. I had shut down the computer in the evening and in the morning the behaviour was there.

The only different is, in the afternoon i haven't connect a external Screen, in the morning i connect to external screen via USB C.

Does anyone have an idea to solve the Problems?

Thanks for help,

Katja

[Katja_bo]

Ask again