Blur Busters Forums

I am playing overwatch, and as discussed by somebody in this forum, it has a weird capping settings that +10fps on your refresh rate. So if i choose 120hzfor ULMB, my fps will be capped at130 fps. My questions will be

1. What happens when the fps in game is capped at LOWER than the refresh rate with ULMB on at 120hz? (eg. 110fps to 120hz) = Scenario A

2. What happens when the fps in game is capped at HIGHER than the refresh rate with ULMB on at 120hz? (eg 130 fps to 120hz) = Scenario B

3. Which scenario, A or B, gives me the lowest input lag?

4. How do i enable fast sync for gtx 980ti? I heard it will not be available for SLI?

Thanks in advance.

My setup is as follows
ASUS XB270HU
2 x GTX 980 ti
i7-6700k

framerate and ULMB don't interact in any complicated way that impacts input lag, though each has their own effect on input lag, and framerate interacts with other stuff like v-sync and fast sync.

Fast sync will cause some amount of judder/stutter, and will add between 0 and 1/framerate of input lag due to the asynchronicity between refresh rate and framerate(compared to vsync off).

ULMB will add less than 1/refresh rate of input lag, as it waits for the whole screen to transition to the new frame before pulsing the backlight.

I have heard nothing about fast sync being incompatible with SLI.

A will have less input lag with v-sync on, B will have less input lag with v-sync off(including fast sync).

Fast-Sync is removed as an option with SLI enabled. So freaking annoying. It's a catch 22. Since you want FPS to be as high as possible for Fast-Sync, you remove the primary means of doing it (SLI) when you enable it.

Basically, it's only good for old games.

Fast sync does nothing (except introduce micro-stutter) unless you get at least a multiple of your refresh rate. So for 120Hz, fast sync is only useful for 240FPS, 360FPS, 480FPS, etc.

For modern games (at least modern games that are graphically demanding), fast sync is useful only in 60Hz mode, where you can get 120Hz-like input lag levels when the game is able to run at 120FPS. And even then there's some micro-stutter. It only goes away once you reach a stable 240FPS.