I own an 8 port Belkin OmiPro2 KVM switch, which is a device used to connect multiple computers to a single display/mouse/keyboard. I've owned this KVM for years and it has exhibited the same symptom since I purchased it, so this is not a new behavior. Basically, when I connect this KVM to a CRT with a standard VGA cable the display looks perfect, but when I connect the KVM to a flat panel display the resulting video looks hot or overdriven. The colors (especially whites) are so intense they overwhelm surrounding colors/text and severely wash out the display.
I have seen this behavior with multiple flat panels, so I think I can safely rule out a problem with a single flat panel and focus on the Belkin.
My suspicion is that the manufacturer purposefully over-drives the VGA video signal with the assumption that the switch may be rack mounted and have to overcome whatever line loss is introduced when routing the signal 10 or 20 feet to the connected display.
In the past, I placed three 100ohm resistors directly on the Red/Green/Blue lines of the VGA with some reasonable success in my output. This had the effect of reducing the over-driven video but introduced 'ghosting' into the output. I suspect this is some sort of impedance matching or frequency-response type problem, but this is definitely outside my normal areas of expertise...
However, feeling like I was on to something, I have googled for how to properly attenuate a VGA signal but with no luck. Perhaps I am using the wrong terminology, or barking up the wrong tree completely.
Can anyone offer any suggestions or a proper circuit that I could try to achieve a better/cleaner/sharper result?