Does the Gert VGA still support 640x480 when using dtoverlay=vga666? I'm trying to set up RetroPie on a 640x480 arcade monitor, but I'm not getting any output. I've tested it on a CRT PC monitor also, and I get an image when I set the resolution to 800x600 and 1024x768, but if I set dpi_group=2 and ...