No direct rendering by default with i810/i815 video

I think it also needs to give 32M ram to i810 to have direct rendering. If this is technically easy it would be very nice.

I'm not particularly fond of forcefully enabling DRI on these chipsets, if 16 bpp color depths are necessary for this.

I don't have one of these handy but would be curious to hear your opinion on how well they run 3D applications and a compositing window manager.

My concern is not so much about the compositing window managers as it is for the 3D screensavers that Ubuntu ships by default. Some of these tend to lock up a system when being rendered in software. There are also several 3D games in the repositories that run much better with DRI enabled.

The i810 and i815 are a couple of those rare chipsets for which there is a free (libre) driver that supports hardware-accelerated 3D. Ubuntu should take full advantage of that so that when i810 and i815 users install Ubuntu, they do not need to tweak Xorg.conf in order to take full advantage of their hardware.

I have a machine which uses i810 video. I set the VideoRam parameter to 16384 and the X screen depth to 16 bits by editing xorg.conf and that allowed me to enable DRI.

To make doing that easier, the "Screens and Graphics" applet should be modified to allow the user to set the screen depth (and possibly VideoRam parameter too). Editing xorg.conf is not very user-friendly. Plus it's a real hassle to switch between 16- and 24-bit.

Apart from DRI, there are other reasons for wanting a 16-bit desktop. It is faster and uses less memory bandwidth. i810 systems are memory-bandwidth-constrained anyway, so reducing bandwidth helps overall system speed.

We won't be changing the configuration to make them use 16bit, instead the driver should be patched to do that if necessary.

Anyway, you should try the newer driver "intel", which could already work correctly.

Actually, this has been fixed by this upload to hardy:

 xserver-xorg-video-intel (2:2.2.0+git20080107-1ubuntu1) hardy; urgency=low
 .
   * Merge from debian unstable, remaining changes:
     - debian/patches
       + 01_fix_compiz_video.diff:
         use xf86XVFillKeyHelperDrawable() to fix video playback with
         compositing enabled.
       + 05_fix_xv_reset.diff
         Playing Xv video after switching modes once the Xv driver is
         initialised causes a lockup, as the overlay regisers need
         re-programming. Ensure such a reset happens after a mode-switch.
     - debian/control
       + Change the maintainer address.
       + Add lpia to the list of architectures.
     - Allow xserver-xorg-video-i810 and xserver-xorg-video-intel to coexist
       until -intel is able to replace it completely.
       debian/control:
       + Nuke Conflicts and Replaces related to -i810.
       debian/rules:
       + Nuke /usr/lib/xorg/modules/drivers/i810_drv.so symlink
       + Nuke /usr/share/man/man4/i810.4 conflict
   * debian/patches/02_force_16bit_i81x.diff:
     - Force 16bit depth on i81{0,5} chips (LP: #178837)
 .
 xserver-xorg-video-intel (2:2.2.0+git20080107-1) experimental; urgency=low
 .
   * New upstream snapshot
     + Clarifies backlight abilities in the manpage. Closes: #451847
     + Will use a functional backlight on older chips now. Newer chips may
       benefit from configured to use something other than the legacy setting
       though. Closes: #451848
     + Fixes exa rendering corruption on some 855GM laptops. Closes: #439210
     + Xv window hidden for a little while no longer causes segfaults.
       Closes: #457587
 .
 xserver-xorg-video-intel (2:2.2.0-2) UNRELEASED; urgency=low
 .
   * Conflict with 915resolution. This driver now handles all of this itself
     and better. Closes: #452803

I just tested a Hardy live CD and "intel" appears to be the default driver instead of "i810" and direct rendering is now enabled by default. Better late than never I guess.

Could someone else confirm this?