Michel Dänzer wrote:
I thought it was an EDID problem,
It's quite possibly indirectly related to that, because if the EDID is available, the X server will derive the DPI from it
It seems that there is some EDID-related problem with 8.18.6 - see my earlier post with the two Xorg.log files, which shows that 8.18.6 does not retrieve correct EDID information from the display. In my case it selects the wrong resolution (1024x768 instead of 1280x1024) and also guesses the DPI incorrectly.