I have a Dell studio 1558 laptop, upgraded to 8GB and a 500gb ssd drive. I connected one 24" monitor via VGA, one 24" using VGA to USB adapter, and one mobile monitor using USB. I tried to connect a 4th monitor using the HDMI port, but when I connect it, the monitor on the VGA port turns off and vice versa. Are the HDMI and VGA ports somehow interconnected where you can only use one?
They could be? HDMI-I is integrated digital and analog. Usually you would connect and HDMI to VGA adapter to get the VGA signal. Sometimes the manufacturer will split the signal to two different connectors for convenience. An HDMI-D and VGA. It's still the same source though. Usually when its done that way, both monitors just show the same signal and mirror each other?
Connect the two monitors and press the Windows Logo key+ P and make sure its set to extend. It should already be on Extend if your using extra monitors but have a look anyway.
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