today i clean under my desktop. i find that "HORI vga box" i rember it not so good graphic but it "cheap" just US$70. there is some pic:
Could you provide a better picture of the SMT chip in the middle of the PCB, or list all the markings on that chip?
Why do cheap upscan converters never have RGB inputs? Surely they're the easiest signals to convert as there's none of that PAL/NTSC decoding or any sort of colour conversion, so it couldn't cost that much to stick in a 21-pin sockect, surely!? Eww.