You are using G-Sync wrong (probably)

Okay, there are lots of misconceptions about  G-Sync, FreeSync, and VSync, especially when it comes to setting everything up for the lowest  possible latency. Some people say you should never turn on any type of sync for competitive  games, or else you’ll increase your latency. So using any type of sync causes slight input  lag so don't use any syncs if your gpus are strong enough.

And you basically just want to look  for any settings that has the word sync in it, so for example I have a setting called  free sync I make sure I uncheck that. Some say you should enable both G-Sync and  VSync at the same time. And some people say you should never even think about enabling V-Sync  because it will increase your latency by a lot.

Now I don't recommend using V-Sync because it will always lead to higher input  delay. Turn this trash off. You know, the tricky part is there’s some  truth to each of these statements.

You can definitely increase your latency a lot with  the wrong settings. Poorly configured G-Sync can easily double or triple your  end-to-end latency. But this is a best-case vs.

worst-case kind of comparison.  There’s definitely more nuance to this. I’ve measured a lot of different settings  combinations, and we’re going to go over the settings you should use and the settings  you should absolutely avoid in a minute.

But why do you even want to use adaptive  sync in the first place? Well, adaptive sync—a. k.

a. G-Sync or FreeSync depending  on which brand of GPU you’re using—syncs your monitor and your graphics  card. That has some key benefits.

I’m using an NVIDIA GPU, and my setup is not  configured to use G-Sync right now. Both my monitor and PC are putting out frames as fast  as they can. The monitor is running at 240 Hz, and the GPU is pushing roughly double that in FPS. 

This creates a lot of so-called tearing. The GPU spits out a new frame whenever it’s ready, but the  monitor can’t keep up. It often gets a new frame mid-refresh and abandons the old frame to continue  with the new one.

With each monitor refresh, I'm getting a mix of older and newer frame  pieces, which can make the image look like it's torn apart. Visually, that’s not ideal. In-game,  this happens multiple times per second, and the result often resembles compression  artifacts—definitely not pleasing to look at.

Still, lots of people play their competitive  games this way because, in theory, it gives the lowest latency. The monitor simply displays  whatever the GPU has ready at the moment, which intuitively sounds like the lowest  latency possible. In contrast, adaptive sync implies that the GPU has to  wait for the monitor to finish a frame, or the other way around.

It’s easy to see where the idea  comes from that adaptive sync increases latency. And, you’ll definitely increase your latency  if you’re just using pure VSync. Historically, this was the only option to sync the monitor and  GPU, but this typically adds quite a few milliseconds of additional latency compared to running uncapped  FPS with default settings and every kind of sync turned off.

But actually, in Overwatch, the default settings with everything  turned off don’t give you the lowest latency you can get. You can easily cut that down by  a few milliseconds, even with G-Sync on. There are two ways you can configure G-Sync  to achieve low end-to-end latency.

What you do NOT want to do is cap your FPS at the maximum  refresh rate of your monitor. Unfortunately, that’s still something that's being recommended a lot online: like a 240 FPS cap for a 240 Hz monitor. Don’t do that, please.

You’re not actually using G-Sync  or FreeSync that way. A cap at the maximum refresh rate isn’t low enough to keep  the FPS inside the adaptive sync range all the time. You’ll still see tearing, at  least at the bottom edge of your monitor.

To eliminate tearing, some recommend enabling  VSync along with G-Sync. While it’s true that this eliminates tearing completely, that VSync  part is tricky. G-Sync is on right now and you’ll notice that enabling VSync automatically caps the FPS to the maximum refresh rate of your monitor or just a frame below—like 239  FPS on a 240 Hz monitor—without using an FPS limiter.

So it worked, right? Well, not exactly.  This is essentially pure VSync without G-Sync, and you might be running these settings without  realizing it.

The latency numbers confirm this: about 25-26 milliseconds, regardless of whether  G-Sync is on or off. Configured like this, G-Sync behaves just like  VSync, which adds latency. To actually use G-Sync as intended and avoid the  latency penalty, you need to ensure the FPS stays inside the adaptive sync range of your monitor  so G-Sync can kick in.

The simplest way to do this is by enabling NVIDIA Reflex in-game. With  G-Sync and VSync on, enabling Reflex acts like an FPS limiter. Reflex on + Boost is usually the  setting to choose for very low-latency G-Sync.

On a 240 Hz monitor, Reflex caps at  224 FPS, leaving some headroom. It can be worth using a manual FPS cap  to squeeze out a few more frames. This is the second method to configure G-Sync for  low latency.

The latency numbers are comparable with both methods, but a manual FPS limiter  doesn’t require your game to support Reflex, and you get a few more FPS. A cap just  3 FPS below the max refresh rate of your monitor ensures both G-Sync and VSync work as  intended with no extra latency. Preferably, use the in-game FPS limiter, but tools like RTSS  or the NVIDIA driver’s limiter work well too.

Both the FPS cap and Reflex methods work  great, resulting in roughly the same end-to-end latency. In both Overwatch and  Valorant, this setup produces lower latency than running uncapped FPS with everything  turned off. Overwatch benefits more than Valorant because it’s more GPU-limited,  where limiting the framerate helps more.

That said, you can achieve slightly lower latency  by running uncapped FPS with NVIDIA Reflex. The effect is small, but  both Overwatch and Valorant show a slight latency reduction  compared to G-Sync configurations. This makes sense when you consider how a  monitor displays images.

Monitors don’t show new images all at once. Instead, they  render line by line, pixel by pixel, from the top to the bottom of the screen. A monitor  using adaptive sync starts drawing a frame and keeps drawing it for the entire refresh cycle. 

A monitor not using adaptive sync will abandon the original frame as soon as it gets a new one  from the GPU and start drawing that instead. If your framerate exceeds your monitor’s refresh  rate, the lower parts of the screen will show bits of more recent frames. Whether this slight  timing advantage is meaningful is up for debate.

Does seeing a reload animation a fraction of  a millisecond earlier help? Probably not. At crosshair level, where I measured these  latency numbers, the advantage is small.

I highly recommend trying both  uncapped FPS and adaptive sync to see which you prefer. Just make  sure to use the right settings. Thanks for watching.

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