Question about sync to exact content framerate

I recently switched from a gsync monitor to a normal 1080p tv and i noticed that leaving this option on still runs the cores at the proper framerate per core instead of a flat 60 fps with it turned off. is there any downside to keeping this option turned on when using a normal 60 hz tv? the scrolling still seems smooth. wouldnt keeping this on be closer to playing on a real console? thanks for any replies. i also have noticed that this option has never worked well with flycast and some games seem to have problems on beetle saturn. running on a 4790k and 980ti.

Yeah, flycast is kinda weird about sync, I think.

The only drawback to leaving it on, AFAIK, is that you’re going to have variable latency that won’t reflect the image you’re seeing on the display. That is, if it takes 17 ms to make a frame (instead of the 16.6666 ms frame time at 60 Hz), it’s going to show the same frame again and your next frame will appear 15 ms later than it should. The next frame will do the same but be 14 ms late, then 13 ms, etc. until it rolls over and starts again.

To me, this is worse than just a constant skewing of the speed by an infinitesimal amount, which your brain adapts to invisibly, though the inter-frame variation probably isn’t a big deal either. (unless you’re already right on your individual threshold for latency acceptance, in which case every few frames it could push you over the edge and feel like it’s stalling your inputs)

This option doesn’t depend on having a VRR display. It’s just that only a VRR display will be able to actually sync to the content framerate. Your TV will show a 1-frame hiccup every so often due to the small FPS/Hz mismatch. An NES for example runs at 60.08Hz. If your TV is 59.94Hz, there is a small difference of 0.14Hz, thus the hiccup once every few seconds.

For emulated systems that have a larger difference (like for example a 57Hz arcade game), the hiccups will come more often and will look much more like stutter.

Anyway, why do you want to keep this setting enabled? If you disable it, RA will adjust the emulation speed slightly so at to get rid of these hiccups if the difference is small (like in the case of the NES, SNES, PS1, and other home consoles.) If the difference is too big (like with some arcade games), RA will not adjust it and the result will be the same as if that option was enabled.

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Thanks for the replies. I was just curious as to how it all works because I was watching a few videos about how some of the clone consoles run on a 60hz tv. Bored and curious during the quarantine so I’ve been playing with a lot of settings with Retroarch.

You can also create modelines for a TV display. Although within some tolerance (1-2Hz). I think flycast by default enables the 60Hz VGA mode so it works fine right off the bat, or so I was told.