Connect 2 pc's to one monitor vga and dvi

status1

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I have 2 pc's one has a vga output and the other has vga but I recently upgraded the video card to a radeon 4750 which only has dvi so on the second computer I have the onboard vga and also the dvi from the new fraphics card

I have a kvm switch that was working fine with the vga only setup but with this new card that only has dvi I can't use the kvm switch for the monitor
I thought I could get away with just some adapters but apparently it's not so simple

The monitor is an Acer which has 2 inputs a vga and a dvi-d that's the one with just the large tab without the 4 pins around then

So with the dvi-d cable between the pc with the dvi card and the monitor it works
I can also use the same cable with 2 adapters to vga on both ends and connect it to the vga ports on the pc and the monitor

Unfortunately using only one adapter so the dvi on one end and vga on the other is not working
I am not getting any signal to the monitor

I was wondering what other options are available
Do I need a different dvi to vga adapter ?

Alternatively what would happen if I connect one pc to the monitor with vga and the other with dvi and run both computers at the same time ?
Am I going to fry both computers or the monitor ?
Am I going to have both images on the screen at the same time ?

 
Solution
shouldn't even need a switch if there already a vga port and a digital port on the monitor
that's what I do on might older stuff plug into the vga \. need to switch screen for the 2 system hit the source or input button on monitor

This is the solution.
You would just have to switch the source, just like on a TV that has 3 HDMI ports, you just select your source.
One PC in VGA, on in DVI, switching sources, BAM done.
Problem is your keyboard won't switch.
 
I think there are two possibilities that might work (you may need to experiment to find out whether they'll really work, though):
1. dvi to vga adapter, but to one side of the kvm switch rather than directly to the monitor. Most video cards with dvi out are dvi-i which carries both digital and analog, even if the monitor's dvi input is digital only.
2. cables directly to the monitor, switch sources at the monitor and use the kvm switch to change which pc the keyboard and mouse are connected to.
 

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Thanks for all the replies
I was thinking along the lines you mentioned but for some reason the dvi to vga adapter is not working if I just use it to convert dvi to vga but it does work if I use it to convert both ends of the cable to vga and connect it to a vga output on the pc
So I am thinking there is maybe one of the signals is not getting through or there is no vga signals coming out of the dvi port on the card even though it has a dvi-i connector
While looking for adapter I have seen ones called active adapters so I am thinking maybe I need one of those
What would be the difference between active and non active adapters ?
Is it just an increase in the signals or are there pinout changes as well ?

As for the input switching on the monitor I am not sure if I have that but I will look into that as well
I have to look for a user manual online for that
 

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Quick update
So I looked into swiching the inputs but for some reason it doesn't work
Here is my setup
I have one computer with a vga cable going to the kvm switch than from the other side of the switch I have a dvi cable with 2 vga adapters (basically another vga cable but I an using these adapters because the kvm switch and the monitor are both females so I am using the adapters as a way to make them male at both ends)

The other computer is going straight from the dvi on the card to the dvi on the monitor
Both computers are working separately with the monitor but not at the same time
When I switch the input from digital to analog on the monitor the screen goes blank for a second and than comes back to the digital screen it never switches to the analog side
Also the setting switches to digital also
It seems like the digital side is overpowering the analog side and it does not stay in that mode while the digital screen is on
So I have to turn off the digital pc to gain access to the analog screen
 

status1

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Ok I finally got it to work although it's a bit tricky
When I was switching the input I had the kvm switch in the digital position which did not have a connection since I was going directly to the monitor with the dvi cable so there was no signal there and that's why it would return to the digital screen I guess that is by design to return to the screen that was active before
So the way I have to do it is that when I switch the input I have to make sure I also switch the kvm to the pc with the vga cable
switching back to digital is easier because when I switch the kvm to digital it looses the signal so it automatically returns to digital screen so I don't have to select the input on the monitor to digital I only have to select it when switching to analog
So It's a little tricky but it does work but I am not using both at the same time that often so this setup is good enough for now
Thanks for all the replies
 

wildcard1978

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shouldn't even need a switch if there already a vga port and a digital port on the monitor
that's what I do on might older stuff plug into the vga \. need to switch screen for the 2 system hit the source or input button on monitor
 
Solution

status1

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Just to clarify
I am only switching the Keyboard and mouse the video I am just changing the input
I don't have an input button so I have to go through the menus so it's a little more than just hitting one button but it does the same thing