High Res HDMI monitor won't run with LXDE

I have a Viewsonic VS13818 HDMI monitor* that runs fine with the BBB Angstrom SW, but not with Ubuntu 13.04 LXDE, installed according to RCN’s instructions at http://elinux.org/BeagleBoardUbuntu#Canonical.2FUbuntu_Images. X windows starts up, shows a greeting, but flickers a lot. When I enter a password, the system emits a fb error (tilcdc 4830.e000.fb: timeout waiting for frame done) and the X system dies.

I suppose this is due to BBB not being able to deal with large HDMI monitors. If so, I need a way to reduce the resolution as X comes up. What’s the best way to do that? LXDE’s autostart file does not seem to work for this (inserting an xrandr command). I don’t have the courage to write an xorg.conf from scratch!

Thanks for any help!

Martin

*Monitor EDID Info:

EDID version 1 revision 3

Section “Monitor”

Block type: 2:0 3:ff

Block type: 2:0 3:fd

Block type: 2:0 3:fc

Identifier “VA2248 SERIES”
VendorName “VSC”
ModelName “VA2248 SERIES”

Block type: 2:0 3:ff

Block type: 2:0 3:fd

HorizSync 24-82
VertRefresh 50-75

Max dot clock (video bandwidth) 170 MHz

Block type: 2:0 3:fc

DPMS capabilities: Active off:yes Suspend:no Standby:no

Mode “1920x1080” # vfreq 60.000Hz, hfreq 67.500kHz
DotClock 148.500000
HTimings 1920 2008 2052 2200
VTimings 1080 1084 1089 1125
Flags “+HSync” “+VSync”
EndMode

Block type: 2:0 3:ff

Block type: 2:0 3:fd

Block type: 2:0 3:fc

EndSection

More info! My attempt at installing 13.04 Raring on the BBB with minimal LXDE desktop failed when logging into LXDE greeter (as noted previously). The (1920x1080) monitor was flickering at 1280x960 res., but this doesn’t seem to have been the problem.

BUT installing 12.10 Quantal, with all the same options chosen, works! I.e. I can get into a LXDE session as expected. The display is not completely stable at 1280x960, but dropping to 1280x800 with xrandr fixes that.

So we may have a 13.04 packaging problem when it comes to LXDE?

Martin

Where are you getting your ubuntu images?

http://elinux.org/BeagleBoardUbuntu#Canonical.2FUbuntu_Images

As provided by Robert Nelson.

Martin Ewing
from Nexus 7 tablet

My personal experience shows this for any monitor I use 13.04 Raring on. It just doesn’t seem to work very well with LXDE. If you use Debian it seems to work pretty well if you want to give that a try.

Debian does seem to be much better than Ubuntu for my HDMI issues. 1280x1024 is good, and the colors are right!

Thanks all.

Martin