What is input lag?
Before explaining Reflex, it helps to understand what it reduces. This section builds the picture from everyday life.
The delay chain
When you click your mouse, a long chain of events follows. The mouse sends a signal, the computer reads it, the game decides what happens, the processor prepares the next frame, the graphics card draws it, the monitor displays it and your eyes see it. Each link takes time. The total time from your click to the first change on screen is called system latency, and many players call it input lag.
Why it matters
In slow games, a delay of a few tens of milliseconds goes unnoticed. In fast shooters, where reactions are measured in fractions of a second, the same delay can make aiming feel heavy and imprecise. Players describe it as the mouse feeling "floaty".
What contributes to it
Mouse polling, the game's own processing, the render queue, graphics card work, monitor processing and the time to scan the picture all add up. The monitor and the mouse are part of the chain, which is why a good monitor matters. Our guide to high frame rates that feel rough explains how steady frames and low delay combine.
A simple measure: milliseconds
Latency is measured in milliseconds. One millisecond is a thousandth of a second. A frame at 60 frames per second lasts about 16.7 milliseconds, so one extra frame of queueing adds roughly that much delay. At 240 frames per second, one frame lasts about 4.2 milliseconds, which shows why high frame rates help.
The render queue: where Reflex steps in
The chief target of Reflex is a hidden queue between the processor and the graphics card.
How the queue forms
The processor prepares frames and hands them to the graphics card. If the processor works faster than the card, frames pile up in a queue. Each waiting frame is old by the time it is drawn, so your input is displayed several frames late.
Why this happens in demanding games
When the graphics card is the limit, the processor races ahead, and the queue grows. The more demanding the game, the longer the queue, and the greater the hidden delay.
What Reflex does about it
NVIDIA Reflex coordinates the game, the driver and the graphics card so that the processor only prepares a frame when the card is ready for it. The queue stays short, and each frame uses fresher input. The latency falls, often with little or no change in frame rate.
Reflex in one sentence
Reflex keeps the pipeline short so your actions reach the screen sooner.
Which cards and games support Reflex?
Support is broad, but it depends on the game.
Hardware
Reflex works on many GeForce cards, including GTX 900 series and newer, according to NVIDIA's lists, so even owners of older cards can benefit. Frame generation needs RTX 40 or 50 cards, and the newer Reflex 2 feature debuted on RTX 50 series cards. Our guide to the RTX 50 series lists the range.
Games
A game must integrate Reflex. Many popular competitive titles do, and NVIDIA publishes a list of supported games. The in-game menu will show an option labelled NVIDIA Reflex, often with choices such as Off, On and On plus Boost.
Monitors with Reflex analysers
Some gaming monitors include a latency analyser, which measures delay between your mouse click and the screen change. If you own one, you can see the effect directly.
Reflex modes explained
The in-game choices are simple once explained.
| Setting | What it does | When to use it |
|---|---|---|
| Off | No Reflex behaviour | Only for comparison |
| On | Reduces the render queue | Most games, most of the time |
| On plus Boost | Also keeps the graphics card clocks high | Competitive play, accepting a little more power |
What Boost adds
Boost stops the card from lowering its clock speed when it is momentarily idle, which can trim latency in some games. It may use slightly more power and heat, so choose it when delay matters most.
Does Reflex lower FPS?
The effect on frame rate is usually small or none. Reflex works by adjusting timing, not by drawing less. Some games even see steadier frame times.
Reflex 2 and Frame Warp
NVIDIA announced Reflex 2 alongside the RTX 50 series in early 2025.
The idea behind Frame Warp
Frame Warp updates the picture at the last moment before it is shown, using your newest mouse movement. The game has already drawn the frame, but just before display, the system shifts the image to match where your mouse has moved since. It then fills in the small gaps that this shift creates with AI. NVIDIA says this can reduce latency substantially in supported games.
How big is the effect?
NVIDIA's headline figure was a latency reduction of up to 75 percent in certain competitive games compared with the same game without Reflex. That figure comes from NVIDIA's own tests, and your results will vary, so treat it as a best case.
Which games and cards
Reflex 2 was announced first for specific competitive games and for RTX 50 series cards, with other RTX cards promised later. Support depends on the game, so check the game's menu and NVIDIA's current list.
Why Frame Warp is not frame generation
Frame generation creates new frames for smoothness. Frame Warp adjusts an existing frame for responsiveness. They solve different problems, and the guide to Multi Frame Generation explains the first.
How to turn Reflex on
The steps are quick.
In the game menu
Open the graphics or gameplay settings and find NVIDIA Reflex Low Latency. Choose On, or On plus Boost for competitive play. Apply and restart if the game asks.
With the overlay
Games with Reflex can show latency statistics in the NVIDIA overlay. Enable the performance overlay in the NVIDIA App, and look for latency numbers while you play. The NVIDIA App guide shows where to find them.
Combine with a frame cap
Capping the frame rate just below your monitor's refresh rate with variable refresh rate keeps latency low and consistent. The site's explanation of VRR, G-Sync and V-Sync covers the pairing.
Measuring latency yourself
You do not have to take anyone's word for it. A few methods let you see the effect of Reflex on your own computer.
Method one: the NVIDIA overlay
The NVIDIA overlay can display system latency in supported games. Turn it on, play for a few minutes with Reflex off, then with Reflex on, and note the numbers. The difference tells you how much delay the render queue was adding.
What to look for
Look at the average figure and at the spikes. A lower average with fewer spikes means smoother, more consistent control.
Method two: a monitor with a latency analyser
Some gaming monitors measure the time between a mouse click and the flash on screen. If you own one, test with Reflex off and on, and compare. It measures the real chain from mouse to pixel.
Method three: the feel test
Play a scene where precise aiming matters. Switch Reflex on and off without looking at the setting, and have a friend change it if possible. If you can tell the difference consistently, you have your answer.
Why numbers and feel both matter
A small number can feel large to a sensitive player, and a large number can feel small to a relaxed one. Use both to decide.
How Reflex fits with other settings
Latency is shaped by many choices, and Reflex works best as part of a plan.
Frame rate
A higher frame rate shortens every step in the chain. Use upscaling to raise it, as explained in our DLSS 4 overview.
V-Sync
Traditional V-Sync can add noticeable delay, because the game waits for the screen. Variable refresh rate with a frame cap is usually a better choice for low delay. The article on reducing input lag in fast combat shows the idea in practice.
Frame generation
It adds a small delay, which Reflex offsets. If you chase the lowest possible delay, leave it off. See whether frame generation adds input lag.
Resolution scaling
Lower internal resolution lets the card finish frames sooner, which cuts latency. This is a quiet benefit of DLSS Super Resolution, and it applies even without Reflex.
Mouse and monitor
A high polling rate mouse and a fast monitor reduce the delay at both ends of the chain. Reflex only fixes the middle, so good peripherals complement it.
Who benefits most from Reflex?
Different players gain different amounts.
Competitive shooter players
These players gain the most, because reaction time decides outcomes. Reflex, a high frame rate and a fast monitor form the core of a low-delay setup.
Players with a slower graphics card
When the card is the limit, the render queue grows and Reflex helps most. Players on a modest card in a demanding game often notice a clear difference.
Controller players
They are less sensitive to small delays, so the benefit is smaller, but Reflex costs almost nothing.
Streamers
Streaming adds load, which can increase the queue. Reflex can help keep the game responsive while the card handles encoding.
Players who may not notice
People who play slow, turn-based or cinematic games rarely notice latency. They can leave Reflex on, but they do not need to worry about it.
How the pieces of the latency chain add up
Looking at each step in turn shows where Reflex helps and where it cannot.
| Step in the chain | What happens | Can Reflex help? |
|---|---|---|
| Mouse and keyboard | Hardware reports your input | No, but a good device helps |
| Operating system | Passes the input to the game | Indirectly |
| Game logic | Decides what happens next | No |
| Render queue | Frames wait for the graphics card | Yes, this is the main target |
| Graphics card | Draws the frame | Indirectly, through steady clocks |
| Display | Shows the picture | No, but a fast monitor helps |
How to use the table
Reflex improves the middle of the chain. Players who want the lowest overall delay should also look at the ends: a quick mouse, a fast monitor and a high frame rate. Treat Reflex as one tool in a kit, not the whole kit.
Why the queue is the biggest hidden cost
The other steps are fairly fixed by your hardware, but the queue can swell or shrink depending on the workload. That variability makes it both the biggest hidden cost and the most rewarding to fix.
Reflex in different kinds of games
Game design changes how much Reflex helps.
First-person shooters
These games are the classic case. Aim, flicks and tracking all depend on quick feedback. Reflex gives a noticeable improvement when the graphics card is busy.
Third-person action games
Dodges and parries depend on timing, and lower latency can make them feel more responsive. The effect is smaller than in shooters but still real.
Racing and flight games
Steering feels crisper with lower delay, though many players use controllers, which hides small differences.
Strategy and role-playing games
Delay rarely matters. Leave Reflex on if it is offered, and do not worry about it.
Rhythm and fighting games
Timing-based games are very sensitive to delay, but many of them have their own latency settings. Check the game's options, and combine them with Reflex if offered.
What Reflex cannot do
Honest limits prevent disappointment.
It cannot fix a low frame rate
If your game runs at 30 frames per second, each frame takes more than 33 milliseconds, and no setting can hide that. Raise the frame rate first.
It cannot change the monitor
A slow panel, a high processing delay or a poor refresh rate adds delay that Reflex cannot touch.
It cannot improve a game that does not use it
Without game support, there is nothing to switch on. Check the list or the menu, and use other methods, such as a frame cap, in unsupported games.
It cannot make you a better player
Lower latency removes obstacles, but skill still decides results. Enjoy the game, and treat the numbers as a bonus.
A short note on Reflex and the NVIDIA ecosystem
Reflex is part of a broader set of tools that NVIDIA offers to esports players, including monitors with built-in analysers and peripherals that report latency. You do not need any of them to benefit. The free software setting captures most of the gain for most players. If you decide to buy extra hardware later, you will already understand what each piece does.
Where to learn more
For the DLSS features that often sit beside Reflex, start with the DLSS 4 overview. For help with the delay that frame generation adds, read the article on frame generation and input lag. If you want to understand the rest of the vocabulary, the graphics card glossary covers every term.
Four example players and their latency choices
These imaginary players show how the same tools lead to different setups.
The ranked shooter player
This player uses a 240 Hz monitor and a strong card. They turn on Reflex with Boost, use a light upscaling mode to push the frame rate high, cap the frame rate just under the refresh rate and leave frame generation off. Their goal is the lowest delay, and they accept a slightly less pretty picture.
The single-player adventurer
This player enjoys detailed worlds on a 4K television with a controller. They leave Reflex on because it is free, and enable frame generation for smooth motion. Delay barely matters to them.
The streamer
This player runs a stream alongside a fast game. They enable Reflex to keep the game responsive, lower the stream resolution when the card is busy and watch the latency overlay to catch trouble early.
The budget gamer
This player has a modest card and a 144 Hz monitor. In demanding games, the render queue grows, and Reflex makes the mouse feel noticeably better. They use Quality upscaling and a frame cap, and they are pleased with the result.
What the four share
Each started with a goal, picked the lightest tools that met it and tested the feel. None needed expert knowledge.
A step-by-step low latency tuning routine
Follow this routine if responsiveness matters to you.
Step one: set the display
Set your monitor to its highest refresh rate in Windows, and enable variable refresh rate if it is available. A display running at 60 Hz wastes a fast card.
Step two: enable Reflex
In the game, turn on NVIDIA Reflex, and choose Boost if you play competitively. Restart the game if it asks.
Step three: raise the frame rate
Use DLSS Super Resolution to lift the frame rate, and lower heavy effects such as volumetric fog. Aim for a frame rate comfortably above your monitor's refresh rate in the lightest scenes, and steady in the heaviest.
Step four: cap the frame rate
Set a cap a few frames below the refresh rate, so that variable refresh rate stays in its working range. The cap prevents the queue from growing, and it reduces heat.
Step five: check the feel
Play a short session, and ask whether aiming feels crisp. If not, check for background programs, a low power mode on a laptop or a processor that is the bottleneck.
Reflex with recording and streaming software
Capturing gameplay adds work and can affect latency.
Capture method matters
Capture methods that hook the game or use the graphics card's encoder have different effects. Hardware encoding through NVENC is usually efficient, while heavy software encoding on the processor can slow the game.
Overlays
Several overlays can add small delays or interfere with frame timing. Keep only the ones you need.
Test before a big match
If you stream competitive games, test your whole setup in a practice session before an important event. A surprise during a match is far worse than a surprise during practice.
Reflex and your power settings
Power management can interfere with latency, so a quick look at the settings is worthwhile.
Windows power plan
On desktops, use the balanced or high performance plan, so the processor does not slow itself between bursts of work. Aggressive power saving can add small, irregular delays that feel like stutter.
Laptop modes
Laptops often have a silent or battery saver mode that limits the graphics chip. For competitive play, plug in and choose a performance mode. The laptop's own software usually offers the switch.
Graphics card power mode
The NVIDIA App offers a power management option that can stop the card from lowering its clocks. Reflex Boost does something similar inside supported games. Use one approach, and watch temperatures.
Heat and noise trade-offs
Keeping clocks high uses more power and makes more noise. If you play for hours, you may prefer Reflex On without Boost, and rely on a high frame rate for low delay.
Why a steady frame rate matters as much as a high one
Latency depends on consistency as well as speed.
Uneven frames feel worse
A game that alternates between very fast and very slow frames feels unpredictable, even if the average looks high. Steady frame times let your hands learn the timing. The guide to 1% lows in the glossary explains why the slowest frames define how a game feels.
How to get steadier frames
Cap the frame rate, close background programs, keep the card cool and avoid overloading video memory. Reflex helps by stopping the queue from ballooning, and a frame cap helps by keeping the load even.
Watch for spikes
If latency spikes appear in the overlay, look for the cause: a heavy scene, a background update or a memory shortage. Fix the cause, and the spikes fade.
Share findings sensibly
If you post your results in a forum, mention your card, monitor, game version and settings, so that readers can judge whether your numbers apply to them. A latency figure without context is hard to use, and a well-described result helps other players far more than a bare number.
Keep a settings note
When you find a setup that feels right, write down the Reflex mode, the frame cap, the upscaling mode and the refresh rate. After a driver update or a game patch, check that none of them has changed, because resets are common and easy to miss.
A word on expectations
You will read dramatic latency figures online, and they usually describe best cases in specific games with specific hardware. Your gain depends on how long your render queue was to begin with. A computer that already runs a light game at a very high frame rate has little queue to remove, while a computer pushing a demanding game near its limit has a lot. Test in the games you actually play, and be pleased with a smaller gain that you can feel, instead of chasing a headline number.
Summary
NVIDIA Reflex shortens the hidden queue between the processor and graphics card, which lowers system latency at little or no cost in frame rate. It is free, widely supported and easy to enable, and it makes the most difference in demanding, competitive games. Reflex 2 adds Frame Warp for further reductions in supported games and first appeared on RTX 50 series cards. Pair Reflex with a high, steady frame rate, a frame cap and a capable monitor for the best result, and remember that frame generation adds some delay that Reflex only partly offsets. Test on your own computer, trust both numbers and feel, and move on to enjoy your games.
Troubleshooting Reflex
| Symptom | Likely cause | What to try |
|---|---|---|
| No Reflex option | Game lacks support | Check NVIDIA's supported list |
| Latency numbers missing | Overlay disabled | Enable the performance overlay in the NVIDIA App |
| Frame rate drops with Boost | Higher power use | Use On instead of On plus Boost |
| No difference noticed | Frame rate already high, or CPU-limited | Test in a demanding scene |
| Stutter with frame generation | Memory or base frame rate | Lower settings, raise the base frame rate |
Keep it simple
Turn Reflex on, check that the game feels good, and move on. You do not need to chase every millisecond.
Myths about Reflex
Myth: Reflex is only for esports professionals
Anyone can benefit, particularly in demanding games. It is free and easy to enable.
Myth: Reflex reduces graphics quality
It does not. It changes timing, not the picture.
Myth: Reflex 2 replaces Reflex
Reflex 2 builds on Reflex and adds Frame Warp. The core idea of keeping the queue short remains.
Myth: Reflex fixes a bad monitor
It reduces delay in the computer. A slow monitor will still add its own delay, so a good display remains important.
A practical low-latency setup
If delay matters to you, follow this checklist.
- Enable NVIDIA Reflex, using On plus Boost if you prefer.
- Use upscaling to reach a high, steady frame rate.
- Cap the frame rate a few frames below your monitor's refresh rate with variable refresh rate on.
- Turn off V-Sync inside the game if you use variable refresh rate.
- Leave frame generation off in fast shooters, or test whether you can live with it.
- Use a mouse and monitor suited to competitive play.
Why order matters
Start with Reflex and frame rate, because they give the largest gains for the least effort. Then fine-tune the rest.
Short glossary for this article
- System latency: the delay from an input to its result on screen.
- Render queue: frames waiting between the processor and graphics card.
- Reflex: NVIDIA's technology for shortening that queue.
- Frame Warp: a Reflex 2 technique that shifts a finished frame to match the latest mouse input.
- Boost: a Reflex mode that keeps graphics clocks high.
- Polling rate: how often a mouse reports its position.
Frequently asked questions about NVIDIA Reflex
What does NVIDIA Reflex do?
Reflex reduces system latency, the delay between your input and the result on screen. It keeps the processor and the graphics card in step, so the game does not build up a queue of old frames. Your actions reach the screen sooner, and the frame rate usually changes little.
Does Reflex lower FPS?
Usually only slightly or not at all. Reflex works by adjusting timing between the processor and graphics card, not by drawing less. The On plus Boost mode keeps clock speeds high and can use a little more power. Test in your game if you are curious.
What is Reflex 2?
Reflex 2 is an update that adds a technique called Frame Warp, which shifts the picture at the last moment to match your newest mouse movement. NVIDIA says it can lower latency further in supported games. It debuted on RTX 50 series cards, with other RTX cards promised later.
Do I need an RTX card for Reflex?
No. Reflex works on many GeForce cards, including some older GTX cards, according to NVIDIA's lists. A game must support it. Frame generation needs RTX 40 or 50 series cards, and Reflex 2 launched on the RTX 50 series, so those features are more limited.
Should I use Reflex with frame generation?
Yes. Frame generation adds delay of its own, and Reflex offsets some of it. Games that offer frame generation integrate Reflex and usually require it. For the lowest delay in fast games, many players still prefer to leave frame generation off.
Is Reflex worth using in single-player games?
It does no harm, and it can make controls feel crisper, particularly in demanding games where the render queue grows. The benefit is smaller than in competitive shooters. If the option is available, leaving it on is a sensible default, because it costs almost nothing.