Screen goes into energy saving mode when connected

[baver]

I have tried to connect two different monitors to a CPU. A LG Flatron L1915S that just goes into power saving mode when started and a Samsung syncmaster 225bw that gives a message "check cable".

Both monitors work on other CPUs. The current CPU does not have a VGA connection. With an adaptor I can connect a VGA or a DVI cable (Flatron only have VGA possibility).

I guess the problem is in the CPU but how can I troubble-shoot? Is it the graphics card (how do I check that?) or can I somehow adjust the monitors to accept the signal from the CPU?

 

[mike1959]

Can you give some more info about what you are using?
Is your PC a known make and model, or is it built up by you?
Both of your monitors are telling you that they are not getting any input, in different ways, and I am guessing you are using a separate Graphic card in an AGP or PCI-express slot on the motherboard.
You say your PC does not have a VGA output, so you only have a choice of one Graphic card, and socket.
So in that case, you have to try it in another pc, OR get a different card to try in your pc.
Can you say if your card has worked before? In your PC or a different one?