Greetings,
Am new to this site and couldn’t find a thread on a subject I’m researching hence this post. I am trying to get smart on how laptop video cards process and output video signals.
I have a Thinkpad A31p laptop with a Mobility Fire GL 7800 video card. I am trying to learn how the card drives both the laptop’s LCD as well as either an external monitor through either the laptop’s VGA port or the docking station’s DVI-out port.
It seems to me that the card would output a digital signal directly to the built-in LCD but would need a digital to analog conversion (DAC) to drive a monitor through the VGA port. I would presume that the signal sent to the DVI-out port would simply be a pass through of the same digital signal sent to the laptop’s LCD.
Would appreciate it if someone could either confirm my thinking or enlighten me. Thanks in advance for your help.
Paul
