I have a Dell C840 notebook computer and am having some strange issues
with colour depth when I change the screen resolution.

Firstly I have a desktop wallpaper which has graduated fill over a
large area and this is how why I first noticed the problem.

When I setup my desktop initially, I set the screen resolution to
1600 x 1200.

If I change the screen resolution to anything less, the apparent
colour depth of the display drops dramitcally, even though Display
settings still reports a colour depth of 32 bits. Changing the
resolution back to 1600 x 1200 does not reverse the problem. Only if I
log off and then long back in will the issue be resolved.

How can I tell the colour depth has dropped, simply because my nice
smooth graduated background now consists of ugly concentric circles.
The problem is not just related to the wallpaper, but any image with a
graduation in colour shows distinct stripes.

Please note, this problems only appears to occur when I am logged into
the machine in a non-administrative account. So my guess as the what
the cause of the problem is would be that certain registry settings
don't have the correct permissions to be modified by non-admins.

Can anyone shed any light on this issue.

Help much appreciated.

Steve

"Steve" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
>I have a Dell C840 notebook computer and am having some strange issues
> with colour depth when I change the screen resolution.
>
> Firstly I have a desktop wallpaper which has graduated fill over a
> large area and this is how why I first noticed the problem.
>
> When I setup my desktop initially, I set the screen resolution to
> 1600 x 1200.
>
> If I change the screen resolution to anything less, the apparent
> colour depth of the display drops dramitcally, even though Display
> settings still reports a colour depth of 32 bits. Changing the
> resolution back to 1600 x 1200 does not reverse the problem. Only if I
> log off and then long back in will the issue be resolved.
>
> How can I tell the colour depth has dropped, simply because my nice
> smooth graduated background now consists of ugly concentric circles.
> The problem is not just related to the wallpaper, but any image with a
> graduation in colour shows distinct stripes.
>
> Please note, this problems only appears to occur when I am logged into
> the machine in a non-administrative account. So my guess as the what
> the cause of the problem is would be that certain registry settings
> don't have the correct permissions to be modified by non-admins.
>
> Can anyone shed any light on this issue.


LCD monitors have a "natural" resolution, the one recommended by the
vendor. Go check the specs on yours to see what resolution is
recommended. Anything else results in graininess due to interpolation.

On May 4, 6:40 pm, "Vanguard" <n...@mail.invalid> wrote:
> "Steve" <sbr...@chem.wayne.edu> wrote in message
>
> news:(E-Mail Removed)...
>
>
>
>
>
> >I have a Dell C840 notebook computer and am having some strange issues
> > withcolourdepthwhen I change the screen resolution.
>
> > Firstly I have a desktop wallpaper which has graduated fill over a
> > large area and this is how why I first noticed the problem.
>
> > When I setup my desktop initially, I set the screen resolution to
> > 1600 x 1200.
>
> > If I change the screen resolution to anything less, the apparent
> >colourdepthof the display drops dramitcally, even though Display
> > settings still reports acolourdepthof 32 bits. Changing the
> > resolution back to 1600 x 1200 does not reverse the problem. Only if I
> > log off and then long back in will the issue be resolved.
>
> > How can I tell thecolourdepthhas dropped, simply because my nice
> > smooth graduated background now consists of ugly concentric circles.
> > The problem is not just related to the wallpaper, but any image with a
> > graduation incolourshows distinct stripes.
>
> > Please note, this problems only appears to occur when I am logged into
> > the machine in a non-administrative account. So my guess as the what
> > the cause of the problem is would be that certain registry settings
> > don't have the correct permissions to be modified by non-admins.
>
> > Can anyone shed any light on this issue.
>
> LCD monitors have a "natural" resolution, the one recommended by the
> vendor. Go check the specs on yours to see what resolution is
> recommended. Anything else results in graininess due to interpolation.- Hide quoted text -

I don't believe the issue is simply a matter of graininess due to me
setting the screen solution to something less that the maximum the LCD
can handle.

If I log into the machine as an administrator I can change the screen
resolution with any apparent change in colour depth. Yes the picture
looks a little more fuzzy but I don't get colour banding on shaded
areas.

If things work correctly for an administrator and then not work for
power users then my guess is that it is a permissions issue with
either the registry or a system file.

Any more ideas?

Steve

On May 5, 12:48 pm, Steve <sbr...@chem.wayne.edu> wrote:
> On May 4, 6:40 pm, "Vanguard" <n...@mail.invalid> wrote:
>
>
>
>
>
> > "Steve" <sbr...@chem.wayne.edu> wrote in message
>
> >news:(E-Mail Removed)...
>
> > >I have a Dell C840 notebook computer and am having some strange issues
> > > withcolourdepthwhen I change the screen resolution.
>
> > > Firstly I have a desktop wallpaper which has graduated fill over a
> > > large area and this is how why I first noticed the problem.
>
> > > When I setup my desktop initially, I set the screen resolution to
> > > 1600 x 1200.
>
> > > If I change the screen resolution to anything less, the apparent
> > >colourdepthof the display drops dramitcally, even though Display
> > > settings still reports acolourdepthof 32 bits. Changing the
> > > resolution back to 1600 x 1200 does not reverse the problem. Only if I
> > > log off and then long back in will the issue be resolved.
>
> > > How can I tell thecolourdepthhas dropped, simply because my nice
> > > smooth graduated background now consists of ugly concentric circles.
> > > The problem is not just related to the wallpaper, but any image with a
> > > graduation incolourshows distinct stripes.
>
> > > Please note, this problems only appears to occur when I am logged into
> > > the machine in a non-administrative account. So my guess as the what
> > > the cause of the problem is would be that certain registry settings
> > > don't have the correct permissions to be modified by non-admins.
>
> > > Can anyone shed any light on this issue.
>
> > LCD monitors have a "natural" resolution, the one recommended by the
> > vendor. Go check the specs on yours to see what resolution is
> > recommended. Anything else results in graininess due to interpolation.- Hide quoted text -
>
> I don't believe the issue is simply a matter of graininess due to me
> setting the screen solution to something less that the maximum the LCD
> can handle.
>
> If I log into the machine as an administrator I can change the screen
> resolution with any apparent change incolourdepth. Yes the picture

I meant to say without any apparent change in colour depth....