TL;DR
Input lag is a chain, not one setting. Fix the big three first: turn Reflex on, turn V-Sync off and cap your FPS just under your refresh rate, and make sure Windows is actually running your monitor at its real refresh rate. That's ~90% of the lag, handled.
Input lag isn't one setting — it's a chain, from the moment you move your mouse to the moment a new frame hits your eye. Every link adds milliseconds. Most "reduce input lag" guides throw 20 tweaks at you with no sense of which ones matter. Here they are, ranked by how much they actually move the needle.
The big three (do these first)
1. Turn on Reflex / GPU low-latency mode
If your game has NVIDIA Reflex (or the AMD/Intel version), turn it on. It stops the GPU from queuing up frames ahead of your inputs. This is the single biggest, easiest latency win there is — bigger than any registry tweak.
2. Turn off V-Sync, cap FPS just under your refresh
V-Sync adds a full frame (or more) of latency — turn it off. To avoid screen tearing without it, cap your framerate a few FPS below your monitor's refresh rate (e.g. 141 on a 144 Hz panel) so the GPU never fully maxes out. Reflex on + V-Sync off + capped FPS is the competitive standard.
3. Actually run your monitor at its real refresh rate
Sounds obvious, but Windows quietly defaults plenty of 144/240 Hz monitors back to 60 Hz. Check Display Settings → Advanced display. Going from 60 → 240 Hz alone removes more felt lag than every micro-tweak combined.
The small stuff (real, but minor)
- Mouse polling rate — 1000 Hz is plenty. Chasing 4000/8000 Hz can cost more CPU than the latency it saves.
- Frame pacing / stutter — steady frametimes feel lower-latency than a high-but-spiky average. Smoothing your 1% lows beats chasing peak FPS.
- Background load — a maxed-out CPU delays your inputs. Close the real hogs (not "every background app").
- Wired peripherals + a good USB port — wireless is fine these days, but a flaky port or hub adds jitter.
What doesn't help (skip it)
Random "input lag" registry packs, sketchy mouse "acceleration fix" .reg files, and
disabling services wholesale — these mostly do nothing measurable and sometimes break things. If a
fix can't tell you which millisecond it removes, be skeptical.
Reflex on, V-Sync off, FPS capped under your real refresh rate. Get those three right and you've fixed 90% of input lag before touching anything advanced.
The advanced 10% — DPC latency, frame pacing, power-plan behavior — is measurable but fiddly, which is what Optimizationmaxxing is for: it probes your actual latency, applies only documented changes, and snapshots every one so you can roll back if a tweak doesn't help on your rig.