Nvidia has a vested interest in improving the gaming experience. Upselling people on the best graphics cards is merely part of the equation. Pushing other hardware and technology to new heights is the second aspect, and periodically we’ll see new advances in the state of the art gaming PC. Today marks the launch of Nvidia’s Reflex Latency Analyzer — not just the software aspect, but actual hardware. Nvidia sent us a kit consisting of a Reflex enabled display and mouse, and we put it to the test.

The best parallel to Nvidia Reflex Latency Analyzer that comes to mind is the launch of G-Sync way back in 2013. It was a bit raw out of the gate, with the first display to support G-Sync actually requiring some hardware modding. The earliest G-Sync monitors were also pretty tame, with 60Hz maximum refresh rates. Today, G-Sync has grown to support G-Sync Compatible displays that don’t even use Nvidia’s G-Sync scaler module, along with higher resolutions and refresh rates of up to 360Hz. Like G-Sync, Reflex Latency Analyzer has new hardware as part of the package, so let’s quickly look at the requirements.

Nvidia Reflex Latency Analyzer System Requirements

• Reflex compatible GPU (GeForce GTX 16 series or GeForce RTX series)
• Reflex compatible monitor (Acer Predator X25, Alienware AW2521H, Asus PG259QNR)
• Reflex compatible mouse (Logitech G Pro, ROG Chakram Core, Razer DeathAdder V2 Pro, SteelSeries Rival 3)
• Bonus points: Reflex enabled game (e.g., Fortnite, Valorant, Call of Duty)

Any Turing or later generation Nvidia GeForce graphics card should suffice, which means a GTX 16-series or RTX 20-series or better. If you have such a GPU, you can enable Reflex in GeForce Experience (the public release with Reflex support should go live on 10/21/2020), and there should at least get some benefit from the low latency mode. This is somewhat akin to AMD’s low-latency driver feature, and basically looks to cut down on how many frames are queued up between display updates.

To get the full Reflex Latency Analyzer experience, however, you’ll also need a Reflex compatible mouse and monitor. The mouse shouldn’t be too big of a problem, but the Reflex monitors, though … you might feel a bit like they’re mugging your wallet. Especially if you’ve recently forked over the money for a high-end monitor. Currently, both Reflex enabled monitors are 360Hz IPS displays, which are basically the fastest and highest quality esports gaming monitors on the market.

One thing to note on the mice is that some of these are updated versions of existing mice. If you already own one of these mice (like the Logitech G Pro Wireless), we’re actually using a pre-release version that supports Reflex. Logitech will have a future mouse that supports Reflex, but existing mice won’t be firmware upgradable as far as we’re aware.

As far as games are concerned, all titles may potentially benefit, but for built-in latency polling and optimizations, another tier of support exists. Fortnite is the first game with full Reflex support, and Valorant, Call of Duty (including Modern Warfare (2019), Warzone, and the Black Ops Cold War variants) also support Reflex. Other games are planning on supporting Reflex as well, and you can still use it in other titles — the latency reduction just might not be quite as large. One thing we like about Fortnite is that it has an option to show a “Reflex Latency Indicator” — a white rectangle that makes it very easy for the monitor sensor to detect the button click.

Let’s be clear that Nvidia Reflex Latency Analyzer isn’t something that everyone needs to run out and buy. Competitive gamers are probably going to be the most eager to upgrade, as reducing latency and just having good tools to measure latency, provides a clear advantage in fast paced games. Casual gamers will likely notice and benefit from Reflex as well, but they’re less likely to pony up for the new top-tier mouse and monitor.

How Nvidia Reflex Latency Analyzer Works

Capturing latency data is normally a complex process. One solution consists of a high-speed camera (1000 fps or more), recording both the mouse and monitor. Click the button and then look for the on-screen result (e.g., weapons fire), and count the frames in between the two. This is a time consuming and arduous process, with some expensive hardware requirements.

Reflex Latency Analyzer gets around that requirement by building a configurable sensor into the monitor firmware, along with a supported USB port for the mouse. When the mouse button gets clicked, the monitor can detect the button press and mark the start time. Then, when the frame with the resulting reaction to the button press appears, the monitor marks that time and calculates the difference.

That’s a bit more complex than it sounds, as the reaction to a button press isn’t always clear. Some guns may show a bright muzzle flash, others might show your character swinging a pickaxe, etc. Fortnite has extra support for Reflex where it shows a white rectangle, which makes capturing the latency data far easier. Other games will likely add support for this in the future, but the important thing is that the  monitor can be configured on where to look for a screen update.

Take a game other than Fortnite, like Call of Duty. The easiest way to have the game detect the reaction to a button press is with a gun that has a bright weapon flash. Go to a darker area, use the monitor OSD to set the ‘sensing’ rectangle to where the muzzle flash first appears, and then proceed to click the mouse button.

This isn’t how you’d normally play a game, of course, but if you’re trying to determine how much latency is present, which is our goal, it suffices. Nvidia’s GeForce Experience overlay is the final part of the equation, with hooks that allow you to display latency data on the screen.

For this initial look at Nvidia Reflex Latency Analyzer, we’re going to use Fortnite, running Creative mode so that we can use the same test area and not worry about getting shot. We’ve selected three Nvidia GPUs, representing the extreme, high, and midrange categories, and we’re testing at multiple resolutions, with and without ray tracing and DLSS where applicable.

One thing that’s important to note is that framerates have a direct impact on latency. If a game runs at 200 fps, that’s basically 5ms per frame, whereas at 40 fps you’re looking at 25ms per frame. While you will benefit in general from the improved latency Reflex offers, for testing we’re using the same area and repeatedly clicking the mouse to measure latency.

Best-case, Reflex seems to eliminate one or two frames’ worth of latency, and in some cases it can cut latency in half.  It’s worth noting that Reflex shuts off at low (<30 fps) frame rates, but in general, gamers would want higher performance as a starting point, so sub-30 fps results aren't really a concern.

Because we’re running on a 1080p 360Hz