Super res issue and GroovyMAME can't display pacman and others

[eoinzy]

Hi,

I have a Radeon R9 380X with calamity drivers.
This is connected from the analog DVI to a VGA connector that goes into my CRT, which is a Nanao MS9-29SU.

I'm having some issues but I think they're all related to one thing, which is Super Resolutions not working on my CRT.
For example, Pacman displays 3 windows side by side. Other games go completely out of sync, depending on their resolution.

My default resolution is 640x480, which obviously works fine, but when i start to go to resolutions like 2560x448 or 2560x384, then i run into sync issues and can't see anything on screen because it goes haywire.
The confusing thing is that when I use VMMaker, my CRT is specifically mentioned so why are there unsupported modes? Or are they supported and there's something wrong with my CRT?
Or maybe i'm doing something wrong? I just picked my CRT in the monitor presets and installed modes.

Thanks in advance.

[eoinzy]

Also, one more thing.
I often use RDP or VNC to connect to my arcade PC for configuration and other things.
I tried to put a custom resolution of 1024x768 but when the modelines are generated, it gets vertically truncated to 1024x560.

It's very difficult to use this resolution to configure frontends. Is there a way I can force a resolution like 720p, just termporarily, while i do my configuration?
Note, the CRT is turned off at this point. I have smart plugs that I can turn on and off from my phone so i can power on the PC and cabinet separately. I do this when i remotely connect to it for config or adding new games

Thanks again