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From [[http://packages.debian.org/xserver-xorg-video-intel|xserver-xorg-video-intel]] version 2:2.9.1-2, KMS is enabled by default on Linux, by the way of the file /etc/modprobe.d/i915-kms.conf. So from Squeeze on, no hand modification should be necessary anymore. From DebianPkg:xserver-xorg-video-intel version 2:2.9.1-2, KMS is enabled by default on Linux, by the way of the file {{{/etc/modprobe.d/i915-kms.conf}}}. So from Squeeze on, no hand modification should be necessary anymore.
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   * In my system (HP/Compaq nx7300 with 945GM) enabling of KMS when loading the i915 module caused blank screen (seems not to be related to incorrect mode, rather the system got suspended or hibernated) when booting the system. Problem could be cured by changing of /etc/modprobe.d/i915-kms.conf to "options i915 modeset=0". What's interesting, booting with "acpi=off" also cured the problem. The same problem occured in a desktop system with 82865G [[http://lists.debian.org/debian-user/2010/02/msg01668.html|(link)]]    * In my system (HP/Compaq nx7300 with 945GM) enabling of KMS when loading the i915 module caused blank screen (seems not to be related to incorrect mode, rather the system got suspended or hibernated) when booting the system. Problem could be cured by changing of {{{/etc/modprobe.d/i915-kms.conf}}} to {{{options i915 modeset=0}}}. What's interesting, booting with {{{acpi=off}}} also cured the problem. The same problem occured in a desktop system with 82865G [[http://lists.debian.org/debian-user/2010/02/msg01668.html|(link)]]

KernelModesetting

This provides faster mode switching for X and console. It also provides native-resolution VTs on some laptops & netbooks which, prior to this, would use some standard mode, e.g. 800×600 on a 1024×600 panel.

To enable Kernel Mode Setting, also known as KMS, you need:

  • a kernel image ≥ 2.6.29 (in Sid since 2009-04-04)
  • supported graphics card

Intel

i915

From xserver-xorg-video-intel version 2:2.9.1-2, KMS is enabled by default on Linux, by the way of the file /etc/modprobe.d/i915-kms.conf. So from Squeeze on, no hand modification should be necessary anymore.

Known bugs

  • vbetool
    • Running this will cause X to fail to start up (black screen except for a static cursor at the top left, can't switch vt), and may cause other problems. (This is a kernel bug.) To avoid this, set SAVE_VBE_STATE=false in /etc/default/acpi-support.

  • linux-2.6
    • Do not load any framebuffer drivers other than inteldrmfb (which is provided by i915) if you enable KMS, else you will probably see hard lockups when trying to start X.
    • If you launch your kernel with a vga=xxx option on the boot line, it will fail (black screen).
  • 945GM
    • Enabling KMS on this chipset may cause a GPU crash: (link)

  • 945GM and 82865G
    • In my system (HP/Compaq nx7300 with 945GM) enabling of KMS when loading the i915 module caused blank screen (seems not to be related to incorrect mode, rather the system got suspended or hibernated) when booting the system. Problem could be cured by changing of /etc/modprobe.d/i915-kms.conf to options i915 modeset=0. What's interesting, booting with acpi=off also cured the problem. The same problem occured in a desktop system with 82865G (link)

Resources