When the HDMI output of the BBB is connected to the HDMI input on the monitor all goes well until the X desktop is started. As soon as X is started the monitor goes into power-save mode. Press cntl-alt F1 to get to a non-gui login and the display turns on. Switch back to F7 and the monitor goes into power-save.
If I use a HDMI to DVI adapter and use the DVI input on the U2410, the X desktop display is OK. I can even use xrandr to change resolution to 1280x1024 (dvi input) which works fine.
I have deduced that when the BBB gets the EDID info from the monitor, it changes to a mode that the Dell U2410 does not like but only with the X desktop.
Anyone have any ideas? I am hesitant to blame the LXDE X server for this but anything is possible.
When the HDMI output of the BBB is connected to the HDMI input on the
monitor all goes well until the X desktop is started. As soon as X is
started the monitor goes into power-save mode. Press cntl-alt F1 to get to
a non-gui login and the display turns on. Switch back to F7 and the monitor
goes into power-save.
If I use a HDMI to DVI adapter and use the DVI input on the U2410, the X
desktop display is OK. I can even use xrandr to change resolution to
1280x1024 (dvi input) which works fine.
I have deduced that when the BBB gets the EDID info from the monitor, it
changes to a mode that the Dell U2410 does not like but only with the X
desktop.
Anyone have any ideas? I am hesitant to blame the LXDE X server for this
but anything is possible.
The odd part is that it is not going into power save…not really. The Dell monitor will go into power save mode if the video being supplied is out of range. I tried shutting off power save mode first and that did nothing. I have a .xsessionrc file and it already contains what you suggested.
I tried swapping cables while it was up and running. When I did that, the monitor briefly displayed what looked like a double image (side to side) and then went into powersave mode.
So what I did was add “xhost +” to the .xsessionrc file
Then I logged in and did the following:
export DISPLAY=:0
xrandr
Screen 0: minimum 320 x 200, current 640 x 480, maximum 2048 x 2048
HDMI-0 connected 640x480+0+0 (normal left inverted right x axis y axis) 518mm x 324mm
1920x1080 24.0
1280x720 50.0 60.0
720x576 50.0
720x480 59.9
640x480 59.9*
In the middle of this I tried a few things and found a work around.
Google got tired of me searching for “debian lde x11 display problem” I finally tried setting the video mode to auto using xrandr and that fixed it. Go figure.
I decided to try a BBB. The BBB has certain features the RPI does not; like multiple UARTs. I have a terminal server that died on me so I am making one from a BBB.
The only thing I wish is that this forum were hosted on something like phpBB3. Google groups is missing certain functions that I rely on.