Re: Picture quality on laptop LCD with i915GM chipset

["Jin, Gordon" <gordon.jin@intel.com>]

SD wrote on Wednesday, May 19, 2010 8:32 AM:
>>> From: Clemens Eisserer <linuxhippy at gmail.com>
>>> Subject: Re: [Intel-gfx] Picture quality on laptop LCD with i915GM
>>> chipset. To: "intel-gfx" <intel-gfx at lists.freedesktop.org>
>>> Date: Saturday, May 15, 2010, 12:56 PM
>>> Hi,
>>> 
>>> Why don't you record a video or take a screenshot to make
>>> at least
>>> clear to us whats going on?
>>> 
>>> - Clemens
>> 
>> I do not blame anyone, I know you all want to help.
>> I tried to take a picture and take a video, but unfortunately 30
>> frame per second can't catch it. Everything looks nice. 
>> I will try to explain again. In compare with kernel up to 2.6.27
>> (because I used Ubuntu, Mandriva), 2.6.33 looks:more brighter, may
>> be more contrast, especially white, it is definitely more brighter
>> although I stated xgamma 0.75. But biggest problem is that colors of
>> the picture are not solid, stable - they are somehow blinking or
>> flickering. Sometime I think may be back lights of LCD panel works
>> different. And after hour or two eyes start notice it, it is looks
>> like colors is not constant, they always changes, little bit but
>> they are "playing". It is very noticeable if I log into different
>> TTY (not graphical) and just start "mc" - it present for eyes.      
>> It is impossible to record, sorry.
>> 
>> Thanks for help.
>> 
>>> 
>>>> I have tried OpenSuse 11.2, which is with newer kernel
>>> and it shows the same bad like Fedora 12. So I decided to
>>> shift on fedora, but unfortunately although Fedora 13 shows
>>> screen better - it is still not usable (actually screen
>>> picture on Fedora 12 was really awful). I have tried to
>>> compare video output on OpenSuse 11.1 and Fedora 13, all of
>>> the has the same, except of "xdpyinfo": on suse it tells
>>> about 3 visuals ( number of visuals:    3), but on Fedora
>>> 13 - 32 visuals. Fedora 12 got 72.
>>>> 
>>>> Problems is not with fonts at all, problem with whole
>>> screen. Font, because it very contrast, is more noticeable.
>>> Also, of course I use freetype for the full hinting.
>>>> Does it happened to all intel chipset, or to only
>>> i915GM, because I of course going to change my laptop, and
>>> it looks like I am not going to by a one with intel video.
>>>> 
>>>> Thanks.
> 
> 
> 
> Dear All.
> 
> At last, I found the problem - it is new kernel 33 and 34, I took
> them from Fedora. 
> I put them to my OpenSuse 11.1 (27 kernel) and boot it up.
> Picture of the screen became unusable. And it is not Xorg with its
> drivers, because except of the kernel everything from OpenSuse 11.1 -
> it is kernel.  
> I do not know how it works with other GPU (intel or nvidia), but mine
> i915GM shows awful screen. 
> I know what is wrong with picture - colors of the pixels. They are
> not static, they change. Little bit, but change. It became more
> noticeable when I just reboot. For example white - it is white, but
> it changes around white, and as color is brighter it is more
> annoying. 

Flickering? Does booting kernel with i915.powersave=0 work?

> May be I am wrong about all of it, I for sure - I am not
> going to use 33 and 34 kernel with i915GM.