U2410 not so easy to switch computers and input sources DVI to VGA

Greetings,

       Maybe someone else has seen this behaviour with this monitor and confirm my suspicion.

I use the monitor extending my desktop using  the DVI connection from my main tower computer.     

Occasionally  I want to hook up the VGA input to my laptop.   ( Both run Win XP SP3 ) 

However simply changing the Input source from DVI to VGA does not let me see anything  from the VGA source ( blank screen). 

I  have tried turning off my desktop ( the DVI input ) and even disconnected the DVI input to the monitor.

Do I have to power off the U2410  and reset it somehow to get the VGA input to work? ????  

 

Experiments - -

        The monitor does detect a  VGA signal from the laptop when I change input source from the  U2410 menu

as it pops up the VGA symbol and a message ( Auto adjustment in progress..) 

It does this again  if I change the resolution and it will also go into power save mode

if I  cancel the "extend my Windows desktop onto this monitor".

Note that I know the VGA signal worked when I first bought the monitor as I tested it with the laptop

before  using it with the tower and DVI.

Currently the DVI input from the desktop is managed by the NVIDIA Control panel software where I  set it

to display a non native resolution and refresh rate   (  1152 x 864  at 75 Hz )   so that it has the same aspect

as the much smaller primary monitor. (  1024 x 768 at  60 Hz ).      

 

The laptop is running an ATI Mobility Radeon x1400   at  1280 x 1024.   

I have tried upping the refresh rate on the laptop to 75Hz  but no help there.   

I have tried launching the ATI Catalyst control panel to see if I can match the resolution of the DVI configuration 

but it does not offer me the 1152 x 864 choice.

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