Laptop Screen Brightness?

  • Thread starter Thread starter Frederick
  • Start date Start date
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Frederick

I have a DELL model PP21L laptop on which the screen is pretty dim. Is
there any adjustment on this laptop that might increase the
brightness?

Thanks

Big Fred
 
Manual is found here; page 25.
http://support.dell.com/support/edocs/SYSTEMS/ins1300/en/om/om_en.pdf
Click to expand...


I should have found that, but I didn't. Anyway thanks. I didn't know
how to control the brightness - now I do.

Thanks again.

Another question-

I also have an Emachines KAV60 and I can't get the display to come on.
A friend's daughter was using it - and he asked me to look at it. I
fear a power saver function might have turned it off. Anyway is it
dead, or can U suggest some way to get it on again? (XP).

BTW - I did Google the subject, but found nothing helpful.
Maybe I missed it.

Big Fred
 
Frederick said:
I should have found that, but I didn't. Anyway thanks. I didn't know
how to control the brightness - now I do.

Thanks again.

Another question-

I also have an Emachines KAV60 and I can't get the display to come on.
A friend's daughter was using it - and he asked me to look at it. I
fear a power saver function might have turned it off. Anyway is it
dead, or can U suggest some way to get it on again? (XP).

BTW - I did Google the subject, but found nothing helpful.
Maybe I missed it.

Big Fred
Click to expand...

Is there any other model number information to go on ? Is
there a serial number sticker on the thing somewhere ?
In a quick search, KAV60 wasn't unique enough.

Paul
 
Is there any other model number information to go on ? Is
there a serial number sticker on the thing somewhere ?
In a quick search, KAV60 wasn't unique enough.

Paul
Click to expand...


Hi Paul

How are U?

I don't see much.

I see

CM-2

WEBCAM OPTIMIZED FOR LOW LIGHT VIDEO CHATTING (BF->Hmmmm)

N214

EMACHINES eM250 SERIES

eMACHINES 250-1187
(BF->numbers are faint and non-distinct)

That's about it!

Thanks

Big Fred
 
There's a manual, but it won't be much help with opening up
your machine. In most laptops you have to remove the
keyboard to get at the video/screen connectors.

http://support.gateway.com/emachines/Manuals/emachines/QS_eMachines_1_0_EN_EM250_.pdf
Click to expand...

It's a netbook with an Atom processor. What's interesting, is this
one is LED backlit. My laptop uses a CCFL backlight, but the
latest illumination type in the panel is LED based. On the one
hand, LEDs can be more reliable, but on the other hand,
it's really a function of all of the electronics involved. And
this computer is relatively cheap.

http://www.amazon.com/Acer-eMachines-eM250-1162-Netbook-Wireless/dp/B00323G71S

Reasons for not lighting up:

1) AC adapter failure plus flat battery.
2) Operating from battery alone and battery is flat.
3) You pressed the function key that causes the display output
to be forwarded to an external VGA monitor.

If there are any status LEDs, you'd want to check whether
the LEDs flash as if a normal boot sequence is occurring.

*******

The power chain might look like this:

DC DC
AC_Adapter ------- Power_Control ---------- Regulators for lower voltages
| VCore, VDimm,
Battery 5V (hard drive/DVD drove),
3.3V, lower voltages.
|
Power for backlight
Power for LCD panel

The power control has to choose where to draw power from,
and decide whether the battery needs to be charged or not.

The motherboard will not come out of reset, until all regulators
are putting out valid voltages. If something was shorted internally,
it would prevent the laptop from starting.

On a desktop, you'd listen for a "beep", to decide whether something
good was happening. I don't know what the netbook uses for feedback.

There is little in the way of useful info, on the Emachines site.

http://support.gateway.com/us/en/emac/product/default.aspx?tab=1&modelId=1862

Paul
 
It's a netbook with an Atom processor. What's interesting, is this
one is LED backlit. My laptop uses a CCFL backlight, but the
latest illumination type in the panel is LED based. On the one
hand, LEDs can be more reliable, but on the other hand,
it's really a function of all of the electronics involved. And
this computer is relatively cheap.

http://www.amazon.com/Acer-eMachines-eM250-1162-Netbook-Wireless/dp/B00323G71S

Reasons for not lighting up:

1) AC adapter failure plus flat battery.
2) Operating from battery alone and battery is flat.
3) You pressed the function key that causes the display output
to be forwarded to an external VGA monitor.
Click to expand...

That's what I was hoping for. I figured the girl might've hit it
without knowing. I need to find what the function key is that would
do that.

Thanks

Big Fred
 
I can't get the screen to light up at all. OTOH, the beeps and other
sounds tell me that this netbook indeed is booting up probably.
I wish I could find the function key that might've turned off the
display. Oh well - may be time for a pro shop look. :<(
Thanks anyway.
Big Fred

 
Paul said:
Try <Fn>+F5

http://www.fixya.com/support/t3123762-turn_vga_out

Paul
Click to expand...

There will be a little picture of 2 screens on one of the function keys. Or
it might even say CRT/EXT or something like that. You hold down the Fn key
(usually near the bottom left of the keyboard) and press the appropriate F
key. I think mine is F7. The screen function has 3 states - internal screen
only, internal+external screen, external screen only. For this reason, press
the function key once and wait a few seconds. If nothing happens, press it
again.

If still nothing happens, then boot Windows into Safe mode and check what
resolution has been set - perhaps Windows is trying to use a resolution that
the screen can't do.
 
There will be a little picture of 2 screens on one of the function keys. Or
it might even say CRT/EXT or something like that. You hold down the Fn key
(usually near the bottom left of the keyboard) and press the appropriate F
key. I think mine is F7. The screen function has 3 states - internal screen
only, internal+external screen, external screen only. For this reason, press
the function key once and wait a few seconds. If nothing happens, press it
again.

If still nothing happens, then boot Windows into Safe mode and check what
resolution has been set - perhaps Windows is trying to use a resolution that
the screen can't do.
Click to expand...

F5 did no good. That function key has the two screens on it.
I can't get the screen to light up even at boot. So, I can't show the
BIOS either. Nada.

I'm thinkin' that the screen is bad.

Thanks

Big Fred
 
Frederick said:
F5 did no good. That function key has the two screens on it.
I can't get the screen to light up even at boot. So, I can't show the
BIOS either. Nada.

I'm thinkin' that the screen is bad.
Click to expand...

Ahh - if you've got no BIOS screen, then there is a physical problem. Could
be lots of things - not necessarily graphics:
The graphics card could be dead, the screen or the connection between the
screen and graphics card could be shot.
The memory could have failed. The motherboard could have died. The chip
could have overheated and gone.

Try taking off some of the case and check connections. other than that,
laptops are tough to diagnose without manufacturer info.
 
Ahh - if you've got no BIOS screen, then there is a physical problem. Could
be lots of things - not necessarily graphics:
The graphics card could be dead, the screen or the connection between the
screen and graphics card could be shot.
The memory could have failed. The motherboard could have died. The chip
could have overheated and gone.

Try taking off some of the case and check connections. other than that,
laptops are tough to diagnose without manufacturer info.
Click to expand...


I will try to take a look at the connections to the screen. I would
think the memory is ok since I can hear the normal, expected sounds of
XP booting up in the dark. The sounds and the time are both what I
would expect. There are two memory cards, I think. So I will remove
each one, one at a time, just to see......

Thanks

Big Fred
 
I will try to take a look at the connections to the screen. I would
think the memory is ok since I can hear the normal, expected sounds of
XP booting up in the dark. The sounds and the time are both what I
would expect. There are two memory cards, I think. So I will remove
each one, one at a time, just to see......
Click to expand...


All I can see is one memory card, an underlying wireless card I think.
No wires. All seems secure.

When I boot this thing, it makes all the normal boot sounds including
completion thereof. The wireless connect led is even blinking. Just
no screen raster.

Thanks again

Big Fred
 
Frederick said:
All I can see is one memory card, an underlying wireless card I think.
No wires. All seems secure.

When I boot this thing, it makes all the normal boot sounds including
completion thereof. The wireless connect led is even blinking. Just
no screen raster.

Thanks again

Big Fred
Click to expand...

Have you tried <Fn>+<UpArrow> or <Fn>+<DownArrow> ?

I see a suggestion they might control screen intensity, but
maybe not for that machine.

The thing is, with a LED backlit screen, if they wanted, they
could have linear intensity control right down to zero. To keep
constant LED backlight color, the LEDs are fed a constant current.
To get variable intensity, they use PWM (pulse width modulation),
at a relatively high frequency. Using that, they can probably
achieve a wider adjustment range, than with a CCFL backlight.

Allowing the user to turn it down to zero intensity, is just
bad UI design. The screen should be limited as to how low it
can be adjusted (for precisely the reason of the symptoms
you're seeing now).

The LCD panel in the em250, has a 40 pin connector on the
back, and a ribbon cable of some sort will plug in there.
And that cable, may provide all the electrical connections.
An LCD panel replacement site, claims it is 1024x600 resolution.
And you can purchase a replacement with either a glossy or
matte finish. If the ribbon cable came loose, it's possible the
computer wouldn't even notice. (I don't think Plug and Play info
flows across the interface cable, so the computer can't tell at
that level, what is there.)

Paul
 
Have you tried <Fn>+<UpArrow> or <Fn>+<DownArrow> ?

yes

I see a suggestion they might control screen intensity, but
maybe not for that machine.

The thing is, with a LED backlit screen, if they wanted, they
could have linear intensity control right down to zero. To keep
constant LED backlight color, the LEDs are fed a constant current.
To get variable intensity, they use PWM (pulse width modulation),
at a relatively high frequency. Using that, they can probably
achieve a wider adjustment range, than with a CCFL backlight.

Allowing the user to turn it down to zero intensity, is just
bad UI design. The screen should be limited as to how low it
can be adjusted (for precisely the reason of the symptoms
you're seeing now).

The LCD panel in the em250, has a 40 pin connector on the
back, and a ribbon cable of some sort will plug in there.
And that cable, may provide all the electrical connections.
An LCD panel replacement site, claims it is 1024x600 resolution.
And you can purchase a replacement with either a glossy or
matte finish. If the ribbon cable came loose, it's possible the
computer wouldn't even notice. (I don't think Plug and Play info
flows across the interface cable, so the computer can't tell at
that level, what is there.)

Paul
Click to expand...
 
Have you tried it with an external monitor (assuming it has
a port)? If it works with an external, the chances are it
is either a failed LCD backlight (common) or the cable/connection
to the LCD has broken or is loose, as Paul mentioned.
HTH
 
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