25 FPS default to 50 Hz instead of 75 (OLED)

The Hobbyist@lemmy.zip to Steam Deck@sopuli.xyz – 13 points –

I was exploring the fps and refresh rate slider and I realized that when setting the framerate limiter to 25, the refresh rate was incorrectly set to 50Hz on the OLED version, when the 75 Hz setting would be a more appropriate setting, for the same reason 30 fps is at 90 Hz and not 60 Hz. Anyone else seeing the same behavior? Is there an explanation I'm missing here?

16

50hz draws less battery so my guess is that they assume players who cap their frame rate at 25 are more in need of battery life over low latency, because why else would you cap it that low?

Idk but that's what I would do

Where did you see it draw less? And by how much? Computing 50 frames per second does draw less than computing 75, but a display to render at 50 or 75, I have not seen anything with respect to consumption, so I'm curious.

I have just heard it mentioned in regards to both the steam deck and smartphones with high refresh rates. I don't know by how much the battery is affected but I know that lower refresh rate draws less. That why smartphones have variable refresh rate and lower their refresh rate to like 1hz when nothing is happening on screen. You can Google it if you want more info

You're confusing rendering and displaying. There is no doubt that rendering at higher fps requires more power draw. But were talking here about a fixed rendering framerate of 25 fps and a case of refreshing the screen at 50 or 75 hz using the same 25 fps rendering. This is not a usual scenario so there is little info about this, hence my initial point.

I don't have exact numbers, but there is some increase in power draw associated with refreshing the screen more frequently. It's certainly nowhere near as impactful as rendering at 50 FPS vs 25, but it's non-zero.

The only reasons (afaik) to have the refresh rate be higher than a locked FPS is to change the timing slightly. But frame times should be the same and the game should look better when the refresh rate is lower. Especially because 25 frames on a 50hz display means 1 duplicate frame per frame as opposed to 2 or so.

What difference does it make updating the screen 75 times per second if you're only getting 25 different images per second? The OLED screen (iirc) doesn't visually change during every screen refresh (if the displayed frame is the same). Limiting to 25/50/75hz would have zero visual difference at 25fps, but would draw more power at higher refresh rates.

If the screen updates 75 times the game doesn't have to wait so long between vblanks so new frames are delivered quicker and input latency is reduced

You can go to the developer settings and use the old frame limiter so you can set the refresh rate and frame limiter settings separately to work around the issue, i think

This is not "incorrect", this is working as intended. It's called frame doubling. There's a toggle somewhere in the settings to separate them again.

It's frame multiplication rather than doubling per se (even if the name says otherwise).

As Tau said, you can change a setting in the developer settings and it will give you separate fps cap and screen frequency sliders. That way you can set it to 25fps and 75hz, or even compare 50hz vs 75hz and see if there's any improvement.