This is REALLY good information (thank you). I hope you can pass it to RT5x creator and also post about which PCBs exhibits this behavior and your settings. Most of the buyers are console users, but obviously many of us PCB users are very curious about its performance.
I'm personally waiting for the OSSC Pro so I can use that rotate feature...
Well, Mike's a good guy and I'm sure he gets enough requests as it is, let alone about stuff he probably doesn't personally have. I think I'll wait until he implements custom modes for PSP and GB Interface first before piling on.
Otherwise, yes, when my arcade PCBs worked with the RT5X, the 1080p OVER mode worked great on my otherwise picky monitor (another reason why I just stick with 240p Line2x on the OSSC for supergun use, because everything takes 480p). 1080p OVER isn't good for Pac-Man though, because that mode crops
just enough to also crop out the edges of the walls, so all the walls look like escape tunnels. This is with me perfectly centering the image with the remote as well. But I play more than just Pac-Man, so without a menu to instantly go to the resolution I need, I'm stuck cycling through a bunch of resolutions I don't need.
To be fair, my RT5X testing with arcade PCBs was done on the initial firmware, so maybe that "Neo Geo fix" firmware did the trick. But when I'm using what I believe is a superior solution with the OSSC anyway (since HD15 forces a separate cable for audio, theoretically making for a cleaner picture)... I won't be retesting any time soon. At least not until I find an 8-pin mini DIN cover because one of these days I'll forget about TTL, and then goodbye expensive equipment...
I too am waiting for the OSSC Pro, or possibly the Pixel FX Morph, for a rotate and zoom feature. And pretty much for one game: The Xbox 360 port of Dodonpachi hidden away in Instant Brain. It's supposed to be the most accurate port, but you can't rotate the screen for a fullscreen TATE or configure buttons. I've already rewired an arcade stick so the top three buttons are A (shot), B (bomb), and X (rapid). A scaler that rotates and zooms would be the last piece of the puzzle, and let's face it, would still be cheaper than getting the PCB!