By skyforbes IDK Why windows/microsoft limits the ability to duplicate one display into three or more displays when the hardware is capable.
PC has 1 vga, 1 hdmi and 1 display port, and each port is connected to a monitor. Windows duplicates only to 1 and 3, 2 and 3, or 1 and 2*. Instead of duplicating 1 screen to 2 and 3.
And I actually use HDMI splitter which doesn't seem to properly work BUT why won't windows allow when there's an available hardware the can support it either way?