DLSS 4 and “Fake Frames”: Why Your FPS Counter Can Lie in 2026
Quick answer: Frame generation (NVIDIA DLSS 4 and AMD FSR 4) inserts AI-generated frames between real ones, so your FPS counter can double or more — but those extra frames don't reduce input lag, and they can add it. A high number no longer tells the whole story. Measure your real display smoothness with the FPS test and understand what the counter is actually reporting.
Why the counter can mislead
Traditionally, higher FPS meant lower latency and a more responsive feel. With frame generation, your GPU renders one frame and the AI creates several more to display between them — DLSS 4 does up to four, and the 2026 DLSS 4.5 update pushes to six. Your counter shows the combined number, but your inputs are still only sampled on the real frames. So 120 "FPS" made mostly of generated frames does not feel like a native 120.
The latency trade-off
Frame generation adds a step, and that adds latency — in some cases tens of milliseconds. Competitive players tend to notice anything above roughly 20ms of added input lag, which is why frame gen is a poor fit for CS2 or Valorant even when the FPS looks great. Technologies like NVIDIA Reflex offset some of it, but the rule of thumb is clear: it amplifies good performance, it does not rescue bad. You want a base frame rate comfortably above about 40 FPS before turning it on.
When to use it
Frame generation shines in demanding single-player games at high resolutions where the base frame rate is already decent and you want extra visual fluidity on a high-refresh display. Turn it off for competitive shooters. Newer tools — including Steam's overlay — now report native and generated frame rates separately, which is the honest way to read your performance.
Get a clean baseline
Because the counter can conflate real and generated frames, start from a clean measurement of what your display and browser actually sustain using the FPS test. Our guide on how to test FPS explains the difference between what your GPU produces and what your monitor can show.
Sources: NVIDIA — Reflex · MDN — requestAnimationFrame()
Frequently asked questions
Why doesn't 120 FPS feel like 120 FPS with frame generation on?
Your GPU renders one frame and the AI creates several more to display between them. The counter shows the combined number, but your inputs are only sampled on the real frames.
How much latency does frame generation add?
Enough to matter in competitive play — in some cases tens of milliseconds, and competitive players tend to notice anything above roughly 20ms of added input lag. NVIDIA Reflex offsets some of it.
What base frame rate do I need before turning it on?
Comfortably above about 40 FPS. Frame generation amplifies good performance rather than rescuing bad performance.
How can I read my real performance?
Newer tools, including Steam's overlay, now report native and generated frame rates separately, which is the honest way to read it.
DLSS 4.5 and what the counter still will not tell you
DLSS has moved on since this article was written: 4.5 added Dynamic Multi Frame Generation, which varies the multiplier at runtime rather than holding it fixed. That makes the headline FPS figure less stable and, for the purpose of this article, less meaningful still.
Generated frames do not advance the game state, so input latency tracks the internal render rate rather than the number on the counter. NVIDIA Reflex is mandatory with frame generation and offsets part of the cost; published measurements put the remaining penalty at roughly 8 to 12 milliseconds in most games, and that penalty does not grow as the multiplier rises from 2x to 4x.
The practical rule is unchanged and now has a number attached. Below roughly 50 to 60fps before generation, the added latency becomes noticeable, because the internal render rate you are actually responding to is already slow. Frame generation is well suited to single-player games on a high-refresh display and poorly suited to competitive shooters, where the internal rate is what decides whether you win a duel.
If you want to know what your display is genuinely receiving, measure it rather than reading the in-game counter — a browser-side frame rate test counts presented frames independently of whatever the game reports.