– While I’ve read that composite and S-Video can output 240p, I thought that the only way to get a progressive output from the Dreamcast was through a VGA box. When I read about it, people were talking about VGA Boxes so that’s why I assumed it only worked that way. I’m probably wrong, so don’t quote me on that.
240p is just a “hack” of sorts for 480i. 480i is basically 240 lines at 60 Hz, but every other set of 240 lines alternates its location so that it appears to our eyes like one 480 line image. 240p just uses the same location for every frame instead of alternating, so you get a 60 Hz progressive image but with scanlines.
In regards to the Dreamcast, what people are talking about is 480p. Composite and s-video are not capable of sending 480p, so you will need a VGA box to do that. SCART can also carry 480p, as previously discussed. All of these connections are capable of carrying 480i and, by extension, 240p (since it’s just a “hack” of 480i). However, as you mentioned, most Dreamcast games don’t support 240p specifically, so you are generally only getting 480i or 480p, the latter of which requires the box.