I bought a monitor that supports both analog and digital but my PC only has a VGA connection. So I am only using analog right now. But from what I have read digital gives off a better picture quality. So, is there a cable that will connect my DVI-D male monitor to my VGA female PC?
Connecting a monitor with digital input to a computer with digital output should give a better quality video signal, mainly because all digital to analog and analog to digital conversions have been removed.
By adding a VGA to DVI-D converter for your monitor you are only just taking the analog to digital conversion and moving it outside of the monitor, since the monitor was doing this internally in the first place.
Is the external A/D converter going to be better or worse than the internal one? It is impossible to say without knowing the equipment. Most likely it will not be as good, since the internal converter was designed with the display in mind.