Question:
[Satellite A100-237] Dithered screen
Hello,
I have problem with my screen on Satellite A100-237. Some colors (lots of them; but some others are displayed correctly, without this problem) looks like dithered, example:
(click again for original size)
The fill on the left should be one solid color, but you can notice some sort of texture (groups of darker pixels) - like if the screen was trying to simulate the color, which it wasn't able to display (technique called dithering, used in GIFs for example). When I change bit depth to 16 bit (I use 32 bit), it is better for some colors (like the one on photo), but it still presists. It is very distracting, especially in videos or games - the picture on the screen move, but this "texture" remains in one place, so it is very easily spotted.
Can I do something with this? Is it a HW or SW fault, or is it considered as "normal"? Does anybody have the same problem? PLEASE ADVISE. THX.
Answer:
Re: [Satellite A100-237] Dithered screen
Try Dead Pixel Buddy and test the screen with all of the colors and see if this "texture" persists. If it does, we're probably looking at a screen/GPU problem rather than a software one.
Also try and see if the "texture" is in place after you shut the notebook down and the screen is inactive with a flashlight.
Answer:
Re: [Satellite A100-237] Dithered screen
All colors from the program (thx) are displayed correctly, but when I use gray, the problem appears (with lightgray the pixels are lighter instead of darker).
I can't observe anything like that on inactive screen.
Answer:
Re: [Satellite A100-237] Dithered screen
Hmm... Mine does that too... in certain greys, for example when you are in the Internet Options box on IE... there is a slight texture to the white thats in the background.
Answer:
Re: [Satellite A100-237] Dithered screen
Whistler> Yes, I see it in Internet Options dialog too. Another place is the gray color around canvas in MS Paint...
What notebook do you have? Same Toshiba?
Answer:
Re: [Satellite A100-237] Dithered screen
From your last posts, I'd say its more software - I'd try reinstalling the GPU drivers for your notebook and see if that does anything.
Answer:
Re: [Satellite A100-237] Dithered screen
So. I tried replacing original drivers with Omega Drivers - same problem. So I uninstalled them and installed original ATi driver from Toshiba (driver from ati.com doesn't work) - still the same.
Even on Windows VGA driver (reboot after uninstalling drivers before installing others) the problem was the same.
It looks like BIOS (I have the latest I was able to find - 1.70) or HW problem.... :-(
Answer:
Re: [Satellite A100-237] Dithered screen
This is very odd - now that we've ruled out its a software problem (based on your last post) try running your notebook throught an external screen and see if you get the same/similar problems.
Answer:
Re: [Satellite A100-237] Dithered screen
I tried with CRT display and nothing like that appeared (no matter of resolution, refresh rate or mode [cloning/extended desktop]) on the external screen...
Answer:
Re: [Satellite A100-237] Dithered screen
I made a simple program showing different shades of gray (RGB color [x,x,x]) in maximized window and noticed something:
1.) color RGB[40,40,40] is perfectly displayed (solid; all pixels are of the same color)
2.) RGB[41,41,41] is same as RGB [40,40,40], but groups of lighter pixels appear
3.) RGB[42,42,42] - is still same, but more lighter pixels appear
4.) RGB[43,43,43] - even more lighter pixels appear (so now it looks like groups of darker pixels in lighter solid color)
5.) RGB [44,44,44] - again displayed perfectly solid color
And it cycles this way every four shades, except that, that in shades higher than 64 (lighter shades), some artefacts appear in the fourth colors too.
So it looks like if the screen was able to display only around 64 shades (or even less) of gray and it is simulating the rest through dithering... Isn't it too few?
This applies to 32 bit. When I lower the bit depth to 16 bit, the texture (groups of pixels) are still visible, but no colors are changing in four shades, and on the fourth, overall color change (the lighter and darker pixels both).
Does anybody have any ideas?
PS: If it is too complicated or incomprehensible, I can make photos. Also if anybody wants that program, write here and I'll upload it somewhere.