Split Screen

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I have a NEC MuliSync LCD 1970 GX monitor.  I am running WinXP Pro SP3
with an NVidia 6600.  About a month ago it started that once and a while
when I start up the computer the monitor comes up with a line across the
middle of the screen.  It looks like the screen may be shifted up half a
screen.  The top half is now at the bottom half.  I know this is an old
monitor but I still like it and use it as the second monitor to my wide
screen.  Am I losing this monitor or is there something simple that
could be wrong?  I have made sure all the monitor connections are tight.
I can straighten the monitor up by turning its power on and off.

Brought to you from Anchorage, Alaska.

Re: Split Screen

Bill Bradshaw wrote:
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"I can straighten the monitor up by turning its power on and off."

This sounds like a perfect workaround, for a tired monitor.

As long as your fix works reliably.


Is this happening on VGA or DVI ?

Try the DVI connection and see if the symptoms change.

VGA has five functional signals to make the image. They
are RGBHV. RGB are carried on mini-coax and are terminated
where the signals get to the monitor. They carry colors.

H and V are for horizontal and vertical sync signals. If
anything were to make an image "move", it would be
a problem with H and V sync. I'm not at all sure how
H and V are supposed to be carried - it's possible the
connection for them, isn't as high a quality electrically.

if you use DVI, the sync carriage and strip out scheme is
different, and the monitor might well work differently
than it does with VGA.

So with VGA, the problem could be video card, cable,
or monitor. With DVI, it would be less likely for
a sync problem to exist in a vacuum. On DVI, if there
was a problem syncing, there might well be a problem
with the pixels in the image as well.

If you try DVI and the problem persists, it could be
that the multisync evaluation of the image, done
by the monitor, is incorrect. And toggling the power
and forcing the evaluation all over again, is
enough to fix it.

If you had a "real sync problem" caused by a bad VGA
cable or bad video card RGBHV output of some sort,
then you'd expect toggling the power on the monitor
to have less effect. (Not guaranteed to fix it every

For VGA, there are a number of alternative output
schemes. One of interest, would be "Sync on Green".
Normally, on a PC, all five signals are used, RGBHV.
But with Sync On Green, H and V are mixed into the
G signal, and stripped out using a PLL at the other
end of the cable. My old Sony CRT supported Sync On Green,
and if I'd wanted, I could have actually disconnected
H and V. But Sync On Green mode, used to make
the image greenish, which is how I could tell what
mode the stupid video card and OS were sending.
I used to have to enter a control panel, and
change it back when that happened. (The computer
used to boot with Sync On Green, and then I had
to change it.) Note that this was eons ago.

I'm not at all sure how you enable Sync On Green on
modern video cards. I can find a posting claiming
you can do it on an ATI video card. And that would
only work, if the monitor also supported Sync On

I'd sooner try a DVI cable, then become desperate like
that and try Sync On Green over VGA.

Just a guess,

Re: Split Screen

It uses a DVI port but the signal is DVI-D.  I am not using VGA but the
monitor can use VGA.


Paul wrote:
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Re: Split Screen

Bill Bradshaw wrote:
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If you think it's otherwise done-for, you can always open it up
for a look. Some of the monitors with integrated power supplies,
have bad caps in the power section. But your issue could be with
the input processing board. There can be several sub-assemblies in
there, which you could try replacing.


I tried a quick search on Ebay, but nothing popped up there. I
wasn't able to find a "disassembly" web page for it either,
to get a better idea of what to look for. Usually the designs
have some level of modularity, and if you can get a part number
off a module inside, you can see if anyone had parted out their
monitor and has it for sale.

The panel itself has some processing on it as well, but as far as
I know, the input processing is responsible for putting the information
in a standard format, for processing by the panel. If the panel is
1280x1024, it's possible the panel only accepts that format, and
the input processing scales any input image to that format.

I know some electronics like that, aren't fun to take apart, because
it's hard to separate the front plastic from the back plastic. I repaired
an "all-in-one" computer once, which required opening up the plastic around
the LCD panel, and it was touch and go not breaking any of the plastic
tabs that hold it together. It helps a lot if you can find a disassembly
web page, because a few pictures takes a lot of the risk out of
opening the plastics.

The only reason I mention this, is your monitor wasn't a cheapy, and
might be worth fixing. I have an expensive monitor, and I also have
one I got on sale for $99. If the $99 one dies, I wouldn't even think
twice about tossing it.


Re: Split Screen

I will just power it down and up until it gives up the ghost permanently
and then make a decision about it.  Thanks for the input.


Paul wrote:
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Re: Split Screen

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Hi Bill,

Right click an empty part of your desktop and select 'NVIDIA Control Panel'.
Once this panel has opened, select the 'Set up multiple displays' from the
Display section in the left hand tree-menu. Looking at the top of this
sub-menu where it says '1. Select the displays you want to use.', ensure
that only ONE monitor is checked.

Hope this helps


Re: Split Screen

Andy wrote:
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I have two monitors.  The NEC 1970 GX is the primary and the HP w2207h
is the secondary.  I run the two monitors distinct (do not clone the
screen) from each other.  The NEC is connected to a DVI and the HP is
connected to a VGA.  This is a very old computer.


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