Dell Inspiron 6000, 915GM video, 1680x1050, 2.6.26 kernel, xorg-server-1.4.2 Gentoo's xf86-video-i810-2.4.0-r1 driver (i.e. the intel-2.4.0 driver with some patches selected from git, see http://sources.gentoo.org/viewcvs.py/gentoo-x86/x11-drivers/xf86-video-i810/files/2.4.0/) worked correctly, as did prior driver versions. Upgrading to xf86-video-i810-2.4.1 (i.e. the intel-2.4.1 driver) resulted in output with a noticeably low color depth. I drew a simple gradient in Inkscape and took some photos - with the 2.4.0 driver, the gradient is smooth, but with the 2.4.1 driver, it's obviously striped. Weirdly enough, the output of xdpyinfo is the same in both 2.4.0 and 2.4.1
Created attachment 18365 [details] photo with 2.4.0 driver (smooth gradient)
Created attachment 18366 [details] photo with 2.4.1 driver (striped gradient)
Created attachment 18367 [details] Xorg log with 2.4.0 driver
Created attachment 18368 [details] Xorg log with 2.4.1 driver
Current 2.4-branch has a lvds dither fix, could you try it?
Yes, the dither fix in http://cgit.freedesktop.org/xorg/driver/xf86-video-intel/diff/?h=xf86-video-intel-2.4-branch&id=d5fd845aab4074ed6d0950551e007ea43fd2d0df fixes my color depth problem. (By the way, as an aside. Is there any way to get a raw text diff from freedesktop's cgit web interface? Because the diffs that cgit displays are in the form of an HTML table - you can't even copy/paste them into a text editor without destroying whitespace. I had to write a greasemonkey script just to turn cgit's output into something I could actually copy into vim.)
You should install git on your machine ;) Mark as closed, will bump another version for regression fixes later.
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