I have a laptop with 2 video outputs 1 hdmi and 1 vga on the vga i have a vga kvk switch and on the hdmi a cable to a smart tv, when projecting the laptop on the smart tv the secondary monitor on the vga switch goes on black, is there a way to use all three monitors?
Probably not,
sometimes graphics cards offer more connections than they can handle at a time. mine also has three outputs of which i can use two simultaneously. You'll probably find info on the manufacturer's site of the computer or gpu.
On my laptop I have the VGA port far from the HDMI and I can easily plugin both.
The problem is not in the ports. It is the hardware. The display card has to support 3 monitors in order for your machine to allow that. Otherwise, you can get only two monitors. Not sure if there is a software that can emulate three monitors on a 2 monitor display card.
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