Comment 22 for bug 378617

Binary package hint: xserver-xorg-video-intel

[Problem]
When the monitor is connected to the DisplayPort, grub and usplash display just fine but X aborts with
(EE) intel(0): No valid modes.
(EE) Screen(s) found, but none have a usable configuration.
Switching to low graphics mode and/or login console is only possible when changing boot options from "quiet splash" to "xforcevesa".
Full resolution only works when monitor is connected via VGA.

[Discussion]
a) DisplayPort + "quiet splash"
With monitor connection Displayport and the standard boot options "quiet splash" the start of X aborts after usplash and displays a failsafe option dialog window where Xorg.0.log can be viewed and options to switch to low graphics mode or login console are presented. But both low graphics mode (see pic) and login console end in screen corruption.
Login through ssh works but xrandr says it cannot connect to screen.

files associated:
dmesg.log
Xorg.0.log
Xorg.failsafe.log
lspci-vvnn.log
displayport-lowgraphics-corruption.jpg

b) DisplayPort + "xforcevesa"
When starting with boot option "xforcevesa" X aborts again but this time switching to the rescue modes works. The low graphics mode first presents a blue dialog (see pic) and after choosing yes X starts with the vesa driver in 1600x1200 mode, but not in native 1900x1200 resolution.

files:
dmesg.xforcevesa.log
Xorg.0.xforcevesa.log
Xorg.failsafe.xforcevesa.log
ddcprobe.xforcevesa.log
xrandr--verbose.xforcevesa.log
displayport-lowgraphics-xforcevesa.jpg

c) VGA
Connected via VGA the native resolution is correctly recognized and activated by the intel driver.

files:
dmesg.vga.log
Xorg.0.vga.log
ddcprobe.vga.log
xrandr--verbose.vga.log

(most recent) System environment:
-- chipset: Intel G45
-- system architecture: 64-bit
-- xf86-video-intel: 2:2.7.99.1+git20090519.09beee37-0ubuntu0sarvatt
-- xserver: 2:1.6.1.901-0ubuntu0sarvatt
-- mesa: 7.6.0~git20090519.d0eccc41-0ubuntu0sarvatt
-- libdrm: 2.4.11+git20090519.f355ad89-0ubuntu0sarvatt
-- kernel: 2.6.30-5-generic #6-Ubuntu SMP Mon May 11 20:46:57 UTC 2009 x86_64 GNU/Linux
-- Linux distribution: mythbuntu 9.10 alpha1 / XFCE + xorg-edgers ppa
-- Machine or mobo model: Foxconn G45M-S (X4500 HD)
-- BIOS version: 080015 (02/26/2009)
-- CPU: Intel Core 2 Duo E7400
-- RAM: ADATA 2x2GB
-- Display connector: DisplayPort
-- Monitor: HP LP2475w, 24", 1900x1200 native resolution