I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm away from
home at the moment but my wife told me over the phone last night that, quote,
"the screen has a dark strip two inches wide down the right hand side"
She says that there's not a sharp line line dividing the dark patch from the
rest of image, so I've discounted any faults with the individual pixel elements
(?).

Doing some Googling it seems that TFT screens have a backlight tube ? I found
this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

.... but at 200 quid for a 17inch screen ! it's not worth the bother and expence
(if that's the problem anyway).

Anybody got any experience or thoughts ?

TIA

--
Mark
Please replace invalid and invalid with gmx and net to reply.

In article , Mark Carver
writes
I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm
away from home at the moment but my wife told me over the phone last
night that, quote, "the screen has a dark strip two inches wide down
the right hand side"
She says that there's not a sharp line line dividing the dark patch
from the rest of image, so I've discounted any faults with the
individual pixel elements (?).

Doing some Googling it seems that TFT screens have a backlight tube ? I
found this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

... but at 200 quid for a 17inch screen ! it's not worth the bother and
expence (if that's the problem anyway).

Anybody got any experience or thoughts ?

Yes, they have a backlight tube, but normally only one or two tubes with
a reflector/diffuser arrangement to do the entire screen. So when the
backlight fails you normally either lose the whole screen illumination
or half of it. But maybe your screen has more.

I have tried to replace one in a laptop, and they are tiny (2mm diameter
glass tube) and very fragile at the ends. Not to mention the problems of
dismantling the panel in the first place.
The other possibility is failure of the inverter module which generates
the high voltage to drive the tube. This is easier to replace, being
outside the LCD panel. If there's more than one driver you can test them
by swapping them around.
--
Tim Mitchell

On Thu, 1 Sep 2005 08:38:04 +0100, Tim Mitchell wrote:

In article , Mark Carver
writes
I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm
away from home at the moment but my wife told me over the phone last
night that, quote, "the screen has a dark strip two inches wide down
the right hand side"
She says that there's not a sharp line line dividing the dark patch
from the rest of image, so I've discounted any faults with the
individual pixel elements (?).

Doing some Googling it seems that TFT screens have a backlight tube ? I
found this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

... but at 200 quid for a 17inch screen ! it's not worth the bother and
expence (if that's the problem anyway).

Anybody got any experience or thoughts ?

Yes, they have a backlight tube, but normally only one or two tubes with
a reflector/diffuser arrangement to do the entire screen. So when the
backlight fails you normally either lose the whole screen illumination
or half of it. But maybe your screen has more.

I have tried to replace one in a laptop, and they are tiny (2mm diameter
glass tube) and very fragile at the ends. Not to mention the problems of
dismantling the panel in the first place.
The other possibility is failure of the inverter module which generates
the high voltage to drive the tube. This is easier to replace, being
outside the LCD panel. If there's more than one driver you can test them
by swapping them around.

Larger panels can have more than 2 tubes, especially on desktop monitors where thickness is not as
limited as on a laptop. They are also probably not as thin as laptop ones.

Here are some tube sources :

http://www.lcdpart.com/doc/ccfl.html
http://www.jkllamps.com/laptop.cfm

"Mark Carver" wrote in message
...
I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm away
from
home at the moment but my wife told me over the phone last night that,
quote,
"the screen has a dark strip two inches wide down the right hand side"
She says that there's not a sharp line line dividing the dark patch from
the
rest of image, so I've discounted any faults with the individual pixel
elements
(?).

Doing some Googling it seems that TFT screens have a backlight tube ? I
found
this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

... but at 200 quid for a 17inch screen ! it's not worth the bother and
expence
(if that's the problem anyway).

Have you read that companies terms? "Note: We will supply backlights as a
supply only with no warranty, we will not accept a return for any backlight
that is broken, or faulty, under any circumstances, or if you find out that
the backlight is not the problem "(they are extremely fragile, and easily
damaged.) If you want a warranty, send the unit in for our fixed price
repair service"

That sounds to me like they wouldn't even replace it if it was broke in
transit!! Avoid.

At a cost of £200 for a tube is it worthwhile, considering you can get a 17"
TFT from aria.co.uk for under £100 now?

http://benq.co.uk/ServiceAndSupport/...uct=577&type=W
Has details about BenQ warranties, If I'm reading it correct then you should
have a 3 year warranty.

Steven.

On Thu, 01 Sep 2005 08:41:32 GMT, Mike Harrison wrote:

On Thu, 1 Sep 2005 08:38:04 +0100, Tim Mitchell wrote:

In article , Mark Carver
writes
I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm
away from home at the moment but my wife told me over the phone last
night that, quote, "the screen has a dark strip two inches wide down
the right hand side"
She says that there's not a sharp line line dividing the dark patch
from the rest of image, so I've discounted any faults with the
individual pixel elements (?).

Doing some Googling it seems that TFT screens have a backlight tube ? I
found this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

... but at 200 quid for a 17inch screen ! it's not worth the bother and
expence (if that's the problem anyway).

Anybody got any experience or thoughts ?

Yes, they have a backlight tube, but normally only one or two tubes with
a reflector/diffuser arrangement to do the entire screen. So when the
backlight fails you normally either lose the whole screen illumination
or half of it. But maybe your screen has more.

I have tried to replace one in a laptop, and they are tiny (2mm diameter
glass tube) and very fragile at the ends. Not to mention the problems of
dismantling the panel in the first place.
The other possibility is failure of the inverter module which generates
the high voltage to drive the tube. This is easier to replace, being
outside the LCD panel. If there's more than one driver you can test them
by swapping them around.

Larger panels can have more than 2 tubes, especially on desktop monitors where thickness is not as
limited as on a laptop. They are also probably not as thin as laptop ones.

Here are some tube sources :

http://www.lcdpart.com/doc/ccfl.html
http://www.jkllamps.com/laptop.cfm

Just found another tube supplier in Germany - very large range - I have bought from these people in
the past :
http://www.backlight4you.com/en/prod...amps/offer.htm

"Mark Carver" wrote in message
...
I have a Benq 731 17 inch TFT screen, it's almost two years old. I'm away
from home at the moment but my wife told me over the phone last night that,
quote, "the screen has a dark strip two inches wide down the right hand
side"
She says that there's not a sharp line line dividing the dark patch from
the rest of image, so I've discounted any faults with the individual pixel
elements (?).

Doing some Googling it seems that TFT screens have a backlight tube ? I
found this firm that do replacements,

http://www.laptopsolutions.plc.uk/lcd_backlights.htm

... but at 200 quid for a 17inch screen ! it's not worth the bother and
expence (if that's the problem anyway).

Anybody got any experience or thoughts ?

TIA

--
Mark
Please replace invalid and invalid with gmx and net to reply.

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

Now I have to wait for my 4 year old home 17" TFT monitor to fail so I can
upgrade.

D

On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

All the best ..

T i m

"T i m" wrote in message
...
On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

All the best ..

T i m

These LG monitors we bought have no DVI...(none of our PC's have DVI
anyhow)..I'm hard pressed to believe the image fidelity could be any better
even with DVI though.

D

On Thu, 01 Sep 2005 10:46:17 GMT, T i m wrote:

On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

All the best ..

T i m


On an analogue interface, the image is converted to a voltage, then converted back to digital in the
monitor, which will inevitably increase noise.
Probably a more important issue however is that the monitor needs to re-generate an accurate and
stable pixel clock timing signal from the analogue sync signal - if it doesn't get this quite right,
resolution and sharpness will deteriorate rapidly as the LCD pixels will not 'line up' with the
generated image.
I must say that as an electronics engineer, I'm rather impressed at how well the monitors I've seen
manage to do this, but it can never be as good as a digital link, and will sometimes be a lot worse.
I would certainly not want to use anything above 1024x768 on an analogue interface.

In article , Mike Harrison
writes
On Thu, 01 Sep 2005 10:46:17 GMT, T i m wrote:

On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

All the best ..

T i m


On an analogue interface, the image is converted to a voltage, then
converted back to digital in the
monitor, which will inevitably increase noise.
Probably a more important issue however is that the monitor needs to
re-generate an accurate and
stable pixel clock timing signal from the analogue sync signal - if it
doesn't get this quite right,
resolution and sharpness will deteriorate rapidly as the LCD pixels
will not 'line up' with the
generated image.
I must say that as an electronics engineer, I'm rather impressed at how
well the monitors I've seen
manage to do this, but it can never be as good as a digital link, and
will sometimes be a lot worse.
I would certainly not want to use anything above 1024x768 on an
analogue interface.

Mine is 1280x1024 on an analogue VGA interface and it is fine. However
it seems to depend on the graphics card, another PC here blurs the
pixels when some graphics operations occur (presumably due to the video
timing changing slightly).

With DVI you are always sure of the pixels in the video being perfectly
lined up with the physical pixels on the LCD panel.
--
Tim Mitchell

Steven Campbell wrote:
"Mark Carver" wrote in message
...

Have you read that companies terms? "Note: We will supply backlights as a
supply only with no warranty, we will not accept a return for any backlig=
ht
that is broken, or faulty, under any circumstances, or if you find out th=
at
the backlight is not the problem "(they are extremely fragile, and easily
damaged.) If you want a warranty, send the unit in for our fixed price
repair service"

That sounds to me like they wouldn't even replace it if it was broke in
transit!! Avoid.

At a cost of =A3200 for a tube is it worthwhile, considering you can get =
a 17"
TFT from aria.co.uk for under =A3100 now?

Indeed

http://benq.co.uk/ServiceAndSupport/...product=3D577=
&type=3DW
Has details about BenQ warranties, If I'm reading it correct then you sho=
uld
have a 3 year warranty.

Thanks for that, I'll pursue that avenue when I return home. I should
still have the receipt, (I bought the monitor in a Tiny store !) but if
not it seems from Benq's T+Cs that they can still accept claims based
upon the manufacturing date. If all else fails that LG model mentioned
by Vortex2 looks tempting !

Thanks again to all for you responces

Tim Mitchell wrote:

On an analogue interface, the image is converted to a voltage, then
converted back to digital in the
monitor, which will inevitably increase noise.
Probably a more important issue however is that the monitor needs to
re-generate an accurate and
stable pixel clock timing signal from the analogue sync signal - if it
doesn't get this quite right,
resolution and sharpness will deteriorate rapidly as the LCD pixels
will not 'line up' with the
generated image.
I must say that as an electronics engineer, I'm rather impressed at how
well the monitors I've seen
manage to do this, but it can never be as good as a digital link, and
will sometimes be a lot worse.
I would certainly not want to use anything above 1024x768 on an
analogue interface.

Mine is 1280x1024 on an analogue VGA interface and it is fine. However
it seems to depend on the graphics card, another PC here blurs the
pixels when some graphics operations occur (presumably due to the video
timing changing slightly).

I've been running 1600x1200 on analog for some years now, it's fine.
I used to have an LG Flatron CRT screen which I have just upgraded to
a Dell 2001FP which is really excellent. It has DVI and analog
inputs. I recently ran it from another computer which happens to have
a DVI output and, to be quite honest, I didn't see any immediate
difference.

With DVI you are always sure of the pixels in the video being perfectly
lined up with the physical pixels on the LCD panel.

--
Chris Green

In article ,
says...
On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

My guess is that it will eventually make kit cheaper because fewer
components are required with digital, but until it's the standard
connection I don't think it will make much difference.

On Thu, 1 Sep 2005 12:03:59 +0100, "vortex2"
wrote:


"T i m" wrote in message
.. .
On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

All the best ..

T i m

These LG monitors we bought have no DVI...(none of our PC's have DVI
anyhow)..I'm hard pressed to believe the image fidelity could be any better
even with DVI though.

D


It's substantially better at higher resolutions because the
interfacing is done entirely digitally and not through digital to
analogue and back again.



--

..andy

To email, substitute .nospam with .gl

In article , T i m
writes

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

If you want to have the pc a long way from the monitor it should make for a
better quality picture and cheaper cabling. Having your pcs in a (well
ventilated) cupboard somewhere could save you a bit of space & keep the
noise down, useful for anti-theft too.
--
fred

Mark Carver wrote:

Anybody got any experience or thoughts ?

Benq do a three year swap out warrenty on flat panel monitors. So give
em a call and they will send you a new one! ;-)

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

T i m wrote:
On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:


We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for the
office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.


I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

I ensured both the new video cards (my and my daughters machines) had
DV outputs, just in case it went that way only in the future?

A friend has a Dell 1920x1440 large widescreen display (like the large
Apple Cinema displays) which has DVI and VGA inputs. He uses it with a
Mac with DVI and a PC/laptop with VGA. He says there's a remarkable
difference between the DVI and VGA inputs, with the VGA showing ghosting
and blurriness which disappears when on DVI. I suspect this is partly
due to the resolution, but also the physical size of the display (19"+
widescreen I think)

I use 1600x1200 on a 19" CRT with no problems.

D

"John Rumm" wrote

Benq do a three year swap out warrenty on flat panel monitors. So give em
a call and they will send you a new one! ;-)

--
Cheers,

John.



Are you sure that backlight replacement won't specifically be an exclusion
of this warranty? I saw something mentioning this on a Sony TFT I just
purchased, but perhaps it was relating to them dying through wear and tear
and not a malfunction.

Alex

Alex (YMG) wrote:

Are you sure that backlight replacement won't specifically be an exclusion
of this warranty? I saw something mentioning this on a Sony TFT I just
purchased, but perhaps it was relating to them dying through wear and tear
and not a malfunction.

I don't recall any restrictions, but then again it has been quit a while
since I last sold Benq TFTs so can't remember with absolute cetainty. No
harm is asking either way.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

T i m wrote in
:

On Thu, 1 Sep 2005 11:02:22 +0100, "vortex2"
wrote:

We recently purchased a stack of these
http://www.scan.co.uk/Products/Produ...oductID=158951 for
the office and the image fidelity (for the price) is completely
awesome....making previous generation TFT's look lousy.

I know we are wandering off topic a bit here shrug but what
'realworld' difference is there between Analogue and Digital input to
these TFT's please?

IMO, substantial. I notice it particularly where fine text is displayed.
With DVI all the verticals are of consistent width and clean. With analog
some appear wider and less distinct. Most pictures seem pretty much the
same on both. However, my experience is with just two graphics cards and
three (different) monitors. Other hardware could produce results that
differ less markedly.

--
Rod