NVIDIA Reflex Low Latency - How It Works & Why You Want To Use It

[jorimt]

Is your GPU usage not maxing out (99%+) when Fortnite drops into the 80's? Because Fornite is not known for being a CPU-bound game, so you must mean your particular CPU is the limiting factor in this case? If it is, all I can suggest is to increase the more GPU-heavy in-game settings and/or downsample your resolution to make the GPU work harder.

As for NVCP settings, G-SYNC, and Reflex, they will not help what you're experiencing, and sometimes with games like Fornite, even having a system that far exceeds the recommended specs won't guarantee you a high average FPS in every match or situation due to internal engine bottlenecks, netcode, etc.

Additionally, if you can't tolerate an inconsistent average framerate, find your lowest average and limit a few frames below it to ensure a constant average (if this prevents max GPU usage, it will also prevent additional render queue latency).

[fried_prophet]

Is your GPU usage not maxing out (99%+) when Fortnite drops into the 80's? Because Fornite is not known for being a CPU-bound game, so you must mean your particular CPU is the limiting factor in this case? If it is, all I can suggest is to increase the more GPU-heavy in-game settings and/or downsample your resolution to make the GPU work harder.

As for NVCP settings, G-SYNC, and Reflex, they will not help what you're experiencing, and sometimes with games like Fornite, even having a system that far exceeds the recommended specs won't guarantee you a high average FPS in every match or situation due to internal engine bottlenecks, netcode, etc.

Additionally, if you can't tolerate an inconsistent average framerate, find your lowest average and limit a few frames below it to ensure a constant average (if this prevents max GPU usage, it will also prevent additional render queue latency).

Thanks so much for taking the time to reply.

GPU usage never gets above 50%, I play on performance mode with all optimized settings (from the Jerian videos and I've tried a few others as well). CPU usage on all cores is often 70-90% according to RTSS.

The frame drops are really the problem. After having read so much about render queues and frame drops, I had come to the conclusion that frame-limiting slightly above my worst drops would help, but that puts me in sub-100 FPS framerates, which is horribly non-competitive. Perhaps limiting to some other average (I've been using Cap Frames as well) could help.

I'm afraid I'm going to have to do a 5800x3d system if i want to play battle royales without frame drops.

[jorimt]

GPU usage never gets above 50%, I play on performance mode with all optimized settings (from the Jerian videos and I've tried a few others as well). CPU usage on all cores is often 70-90% according to RTSS.

What resolution are you running at? I'd assume 1080p or lower based on the GPU usage, along with graphical settings at lower values perhaps?

The frame drops are really the problem. After having read so much about render queues and frame drops, I had come to the conclusion that frame-limiting slightly above my worst drops would help

Framerate limiting will do nothing to increase the average framerate, which is dependent entirely on the capabilities of the given system in combo with the optimization of the game engine (and whether it's CPU or GPU-heavy).

It sounds like you need a stronger CPU, or again, you need to get your existing system to utilize your GPU more by upping GPU-heavy in-game graphical settings and internal resolution.

[7Z7]

Is it possible to increase the FPS limit?

Nope.

I guess it's always better to activate Reflex at 325 fps than to deactivate it and be with 354 fps?

Only if your GPU usage is maxed the majority of the time; if your framerate can reach your set limit without maxing your GPU, Reflex will not reduce latency further.

Thank you for your answer

After many tests, I noticed that I had less input lag and latency with Reflex disabled

It's strange but I left it at 354 fps with G-Sync and V-Sync

[woland]

It sounds like you need a stronger CPU, or again, you need to get your existing system to utilize your GPU more by upping GPU-heavy in-game graphical settings and internal resolution.

Can you please elaborate this part? How can one determine which settings can be used to force more workload onto the GPU from the CPU?

[jorimt]

Can you please elaborate this part? How can one determine which settings can be used to force more workload onto the GPU from the CPU?

Primarily by increasing graphical settings until you see a GPU usage increase. What settings are more GPU-dependent varies by game.

One thing that is always more GPU-dependent is resolution; the lower the resolution, the more CPU-dependent things become at otherwise identical settings, so if you're seeing low GPU usage, try downsampling your resolution (especially if you're still playing at 1080p), either with an in-game internal resolution scaler or external options like DSR.

For instance, when review sites test CPU performance, they lower the resolution (sometimes along with graphical settings) to try and force a CPU-limited scenario.

Discounting any frametime performance differences, at resolutions like 1440p and 4k, you can get away with using any recent i5-level+ CPU as long as you have a powerful enough GPU in most modern AAA games. I.E. you'll get roughly the same average framerates when pairing a RTX 3080-level+ GPU with a 8700k as you will when pairing it with a 12900k at 1440p+, so long as the game in question is GPU-dependent enough.

[jorimt]

After many tests, I noticed that I had less input lag and latency with Reflex disabled

It's strange but I left it at 354 fps with G-Sync and V-Sync

For what it's worth, I tested Overwatch latency levels with Reflex vs. the in-game limiter in non-GPU-bound scenarios, and I measured no average latency differences:
viewtopic.php?f=5&t=9151&p=72211#p72182

That said, yeah, again, if your GPU usage isn't maxed in Overwatch, you don't really need Reflex enabled.

Reflex is much more useful for eye-candy AAA single-player games where framerate matter less than visuals and you want to crank everything up without incurring a render queue latency penalty.

[TheKelz]

Thank you for this thread.

Quick question. I'm playing BF2042 on a 144HZ FreeSync monitor (GSync compatible). I've chosen to go with GSync + NVCP VSync + Reflex Boost (which limits FPS to 138) with this game, but I can still notice input lag compared to GSync and VSync off (but it becomes stuttery/jittery as well). Would putting FPS cap lower than 138 help with this input lag?

[jorimt]

I've chosen to go with GSync + NVCP VSync + Reflex Boost (which limits FPS to 138) with this game, but I can still notice input lag compared to GSync and VSync off (but it becomes stuttery/jittery as well). Would putting FPS cap lower than 138 help with this input lag?

The only input latency difference between G-SYNC on + V-SYNC on + an FPS limit within the refresh rate and G-SYNC off + V-SYNC off is tearing; the former won't, the latter will.

Tearing artifacts are causing both the "stuttery/jittery" feel, as well as any slightly faster frame delivery due to those very tears in the G-SYNC off + V-SYNC off scenario. G-SYNC prevents tearing by dynamically steering the tearline off-screen.

If you're using G-SYNC on + NVCP V-SYNC on + Reflex Boost (the last of which is both preventing the framerate from exceeding the G-SYNC range, as well as any additional render queue latency [unrelated to G-SYNC operation] whenever the GPU is maxed), then it's as low latency a tear-free syncing method can get on a 144Hz monitor.

So no, a lower-than 138 FPS won't reduce latency further in your particular scenario. Any lower latency would require a higher max Hz (aka larger G-SYNC range) and/or tearing at that same Hz.

[SvenL]

It sounds like you need a stronger CPU, or again, you need to get your existing system to utilize your GPU more by upping GPU-heavy in-game graphical settings and internal resolution.

Isn't that just possible with Reflex On + Boost? I thought the additional option was intended for this purpose so that the graphics card still clocks high in a CPU-bound case.