A frame rate limiter that can be used on your Valve laptop (which is a file steam surface good battery life) may have a slight side effect.
The redditn Dacvak has published a new Steam Deck synopsis and its frame rate fixing solution. He only ran a game during his tests, Rogue Legacy 2. Initially, he ran latency tests on Valve hardware because he wanted to see how much more a DualSense controller would make when using a Steam Deck tied to a TV. On its screen, that was only 12ms, so that resulted in a relatively low response time.
But something interesting happened during the tests. In the Steam Deck performance menu, when I activated the frame rate limiter, an amazing amount of input latency appeared, which is more or less proportional to its size. Without a dock, running barefoot, the input lag was 31.8ms, but with the 60fps limit it was already 75.8, and limited to 30fps, it was 145.9ms! (This means that what we want in the game takes about a tenth of a second to happen.)
At 50Hz, the input lag is 32.5ms, but it is limited to 50fps, which is already 94.2, and the 25fps limit is 186.1ms. At 40 Hz, 34.3 ms is unlimited, which is already 121.1 when reaching 40 fps, and at 20 fps it is already a detectable amount, since 232 ms corresponds to about a quarter of a second, which can be very harmful for more species (Perhaps RPGs are an exception…).
Then Dacvak also tried a game with a built in frame rate limiter (like Rocket League), but there was no additional input lag here. You don’t have to think about VSync here. You have switched Steam Deck to the appropriate refresh rate. I set Rocket League to 50fps (since there are no 40 options) and then set my laptop screen to 50Hz. There was a slight but not significant increase in input lag so currently it seems like a better solution to limit performance with an option in games.
SteamOS recently got a Beta 3.2 patch to limit the refresh rate within games, but it also came with a fan curve that the operating system manages (for example, you can set when to spin more aggressively and when to stay cool at low rpm).
source: WCCFTech
