Does an HDMI that connects your LCD monitor to your PC - make it high definition and is that all it does?

Answer 1

HDMI is the standard interface for HD video today. It is only a cable connectin and it carries whatever signal is given to it to carry. The signal can be standard definition video, high definition video or it can be DVI computer display data.

What it won't do is to make a signal into high definition. It will only carry signals as they are generated. However, if it's connected from a PC to a television, the PC can interrogate the television, find out the native resolution of the television and then generate a suitable signal. That guarantees the best possible quality of image. Not all PCs will do this so you may still need to set the output resolution manually.

Also, be aware that DVI is compatible with HDMI in that they handle video signals in the same way. Unlike HDMI, DVI does not support audio. Therefore, a DVI to HDMI cable will connect PCs with DVI outputs to televisions that only have HDMI ports.