Dreamcast High Definition cables/boxes

[JC34]

Hello,
I recently purchased a Dreamcast and would like to get some sort of high definition cable or box for it. Since I'm new to the Dreamcast, I have no idea what to get. I've seen many youtube videos on the subject but I can't decide. So I decided to come here and ask "the pros" for some advice. So just put down what cable or box you think I should get in the reply section. Any price is fine. Also, does having this cable allow me to use my Dreamcast in full screen or is that just not possible?


Thanks.