Talvez o seu KVM não implemente corretamente Canal de dados de exibição ou tenha alguma falha ou precise de alguma configuração?
Some KVM switches (keyboard-video-mouse) and video extenders handle DDC traffic incorrectly, making it necessary to disable monitor plug and play features in the operating system, and maybe even physically remove pin 12 from the analog VGA cables that connects such device to multiple PCs.
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The Display Resolution control panel applet allows the user to disable this driver's Plug and Play features and manually select any resolution or refresh rate supported by the video card.