Intel-driver does not enable dithering on Dell Latitude C400. The result is that there is "banding" instead of a smooth transition between colors. It is especially apparent when there is any kind of gradient on the screen. The problem is probably that the C400 has 6-bit LCD-panel and Intel-driver doesn't probe the panel properly. The driver doesn't know that the dithering should be enabled for this panel.
I'll need some logs (dmesg, X log and other info requested in http://intellinuxgraphics.org/how_to_report_bug.html), but it may be a a dup of #21446 if you're using KMS.
Created attachment 25305 [details] Xorg.0.log
Created attachment 25306 [details] dmesg
Created attachment 25307 [details] xrandr output
Created attachment 25308 [details] xorg.conf
Distribution: Arch Linux Kernel: 2.6.29.1 Xorg version: 1.6.1 Intel-driver version: 2.3.2 libdrm version: 2.4.9 DRI-driver version: 7.4
Created attachment 25315 [details] vbios
Does this still happen on more recent versions? AFAICT we set the dither bit on all DVO attached panels, so please re-open if it still fails with the 2.7.1 driver for example (or file a new bug if you see a different issue).
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