Its a good first step into the VGA/HDMI Dreamcast game.
That was one of the first cables I used for VGA output, where it then went into a variety of VGA-HDMI converters. (1st a small laptop one, then a $30 ish one from amazon, which did a better job preventing image noise).
For me, my final solution was doing an internal VGA+3.5mm+switch mod at the back of the console, and plug in a Atlona AT-HDView directly into that port. That one did the best in converting the VGA signal to true 480p (not 640x480 via HDMI like the pass through cables & cheep HDMI box's)
Running a properly time 480p signal into my TV allowed it to be displayed properly with color, scaling, etc. Where as a 640x480 via HDMI signal limited my tv's processing and color settings since it assumed it was bring plugged into a computer, and not a console or set-top box. Not all TV's behave this way, but all my vizios did.