Dell XPS13 screen almost completely dark

My Dell XPS 13 (9360, Intel UHD Graphics 620, Ubuntu 21.10) had the following hardware failure:

• On startup, the screen remained almost dark, i.e., if I dimmed the light, I was able to see everything, including colors (but just barely so).

• Software brightness changes were indicated but no changes in brightness happened.

• The integrated graphics test passed without complaining (and I was able to see it in a dark surrounding).

• Also the display's brightness was the same starting the BIOS on startup.

• The computer was perfectly working using an external monitor connected via HDMI.

My own uninformed guess would have been that my display's background light was broken.

I sent in the computer to Dell and now got the reply that the motherboard is broken, together with a quote to replace it.

Question: Is their diagnostics that the motherboard is broken reasonable given this setup?

Solution 1:

I sent in the computer to Dell and now got the reply that the motherboard is broken, together with a quote to replace it.

Ask them if they guarantee the repair for 6 months or a year.

Normally a dim screen light is a backlight issue as you note. But if the backlight failed as the result of a motherboard circuit failure, then it could be the motherboard.

So two things:

(A) If you are willing to repair, you need a warranty that the repair is correct and will hold.

(B) If the repair is not economical, this may be the time to replace the computer.

I trust this helps your thinking.