You can have a monstrous RTX 5090, a 4K 120–144 Hz display and still end up with:
Horizontal tearing across the screen
Juddery camera pans
Weird stutter when FPS dips
Or a “floaty” feel from input lag
Most of that comes down to how you handle sync:VRR, G-Sync, FreeSync and V-Sync.
This article explains, in practical terms for RTX 50-series PC gamers in the UK:
What each tech actually does
Which one(s) you should use on a 4K monitor vs 4K TV
The best setting combos for cinematic, high-refresh and competitive play
How to avoid the classic mistakes that ruin smoothness
1. Why Sync Tech Matters More Than “High FPS”
If you’ve already read your own line “high average FPS ≠ genuinely smooth gameplay”, this is the other half of that story.
1.1 Refresh rate vs frame rate
Refresh rate (Hz) – how often your display redraws the image (e.g. 60 Hz, 120 Hz, 144 Hz).
Frame rate (FPS) – how many frames the RTX 5090 is pumping out every second.
If those two are out of sync, you get:
Screen tearing – parts of two frames on screen at once, giving horizontal “rips”
Judder – uneven motion when frame delivery doesn’t line up with refresh
Perceived stutter, even when your FPS counter looks “good”
Sync tech exists to stop that mismatch and make motion feel continuous.
2. What V-Sync Actually Does (and Why It’s Not Enough on Its Own)
V-Sync (Vertical Sync) is the oldest approach and is still in almost every game menu.
2.1 How V-Sync works
V-Sync:
Locks frame output so the GPU only presents a new frame when the display starts a new refresh
Effectively caps FPS at (or near) the display’s refresh rate (e.g. 60 FPS on 60 Hz)
Eliminates classic tearing, because you never see part of the “old” frame and part of the “new” one at once
2.2 The downsides
On its own, V-Sync has two big issues:
Input lag
Frames can sit in a queue waiting for the next refresh slot
You feel this as mushier mouse/aim response, especially in shooters
Stutter when FPS < refresh
If your GPU can’t keep up (e.g. 50 FPS on a 60 Hz screen), V-Sync may repeat or drop frames
This shows up as noticeable judder / stutter during heavy scenes
So V-Sync solves tearing but creates a lag vs stutter trade-off, especially painful at 4K where FPS is harder to keep consistently above your refresh.
That’s why VRR (Variable Refresh Rate) is so important for an RTX 5090.
3. VRR – The Core Idea Behind G-Sync and FreeSync
VRR (Variable Refresh Rate) lets the display change its refresh rate on the fly so each refresh waits for a complete frame from the GPU.
Instead of the panel ticking away at a fixed 120 Hz while your GPU fluctuates between 77–108 FPS, VRR means:
GPU renders a frame → display refreshes right then, at that moment
If FPS dips, the screen temporarily runs at a lower refresh rate instead of showing torn frames
Result:
Far less tearing
Much smoother motion when FPS moves up and down
Fewer obvious stutters as long as you stay inside the display’s VRR range
VRR isn’t tied to a single brand:
On DisplayPort, it’s part of VESA Adaptive-Sync (DP 1.2a+).
On HDMI 2.1, you get HDMI VRR, plus related gaming features like ALLM (Auto Low Latency Mode).
HDMI 2.1 doesn’t magically guarantee VRR though – the TV/monitor still has to implement it and sometimes even gets it via firmware updates.
4. G-Sync: NVIDIA’s VRR Ecosystem
G-Sync is NVIDIA’s branding and ecosystem around VRR.
There are three main “flavours” you’ll encounter with an RTX 5090:
4.1 G-Sync (with hardware module)
Uses a proprietary NVIDIA module inside the monitor
Offers very wide VRR ranges, in some cases down to 1 Hz
Aims for extremely tight validation on ghosting, flicker and latency
These displays tend to be more expensive but are “gold-standard” for smoothness and low artefacts.
4.2 G-Sync Compatible
Most modern “G-Sync” monitors and TVs you’ll see now are labelled G-Sync Compatible:
They use VESA Adaptive-Sync (the same standard FreeSync sits on)
NVIDIA has tested and certified them to work properly with GeForce GPUs
In practice:
They behave very similarly to FreeSync monitors
You get VRR over DisplayPort and often HDMI
You still need to enable VRR / Adaptive-Sync in the monitor’s OSD in many cases
4.3 What this means for your RTX 5090
If your 4K monitor or TV is:
G-Sync or G-Sync Ultimate – fantastic; you get premium VRR behaviour
G-Sync Compatible – still excellent; ideal pairing for a 4K RTX 5090 rig
Not labelled, but supports FreeSync/Adaptive-Sync – it may still work with VRR on an RTX card; you just might not have NVIDIA’s certification safety net
5. FreeSync: AMD’s VRR Brand (But Relevant to RTX Users Too)
FreeSync is AMD’s branding for VRR displays based on VESA Adaptive-Sync:
Built into DP 1.2a+; monitor manufacturers can add it with little extra cost
Often cheaper than proprietary G-Sync module displays
There are tiers:
FreeSync – basic VRR support
FreeSync Premium – adds minimum 120 Hz at FHD and low framerate compensation
FreeSync Premium Pro – adds GPU-side HDR tone-mapping requirements
Modern NVIDIA GPUs (including RTX 50-series) can use many FreeSync / Adaptive-Sync monitors as G-Sync Compatible, giving you VRR without needing a proprietary module.
This is great news for your wallet: you can often pick a good 4K FreeSync / G-Sync Compatible monitor or TV and enjoy full VRR on an RTX 5090.
6. So… What’s the Difference in Practice?
Short version:
V-Sync
Oldest solution
Fixes tearing on fixed-refresh screens
Adds input lag and can introduce stutter when FPS < refresh
VRR (Adaptive-Sync / HDMI VRR)
Core tech that changes refresh per frame
Greatly reduces tearing and judder within the VRR range
G-Sync / G-Sync Compatible
NVIDIA’s VRR ecosystem
G-Sync module = premium experience
G-Sync Compatible = validated Adaptive-Sync / FreeSync displays
FreeSync
AMD’s VRR brand on Adaptive-Sync
Various tiers (Premium, Premium Pro) with extra requirements
Widely supported and often cheaper
On an RTX 5090, you’re essentially choosing which flavour of VRR display to pair with, then deciding how to combine VRR with V-Sync and FPS caps.
7. Best Settings for RTX 5090 + 4K Monitor
Assuming a 4K 120–144 Hz G-Sync / G-Sync Compatible / FreeSync monitor on DisplayPort:
7.1 NVIDIA Control Panel basics
In Set up G-Sync:
Enable G-Sync / G-Sync Compatible for your main display
In Manage 3D settings → Global:
Power management mode: Prefer maximum performance
Low Latency Mode: On (Ultra per-game for GPU-bound titles)
V-Sync: Pick a global pattern and stick to it (more below)
7.2 Two reliable patterns
Option A – Smooth and tear-free (great for single-player)
G-Sync / VRR: On
NVIDIA V-Sync: On (global)
In games: V-Sync Off
FPS cap: 2–3 FPS below refresh (e.g. 117–118 on 120 Hz, 140–141 on 144 Hz)
Result:
No tearing
Very consistent frametimes
Latency still excellent at high refresh
Option B – Latency-first (more competitive)
G-Sync / VRR: On
NVIDIA V-Sync: Off
In games: V-Sync Off
FPS cap: your choice, usually just below refresh to avoid crazy spikes
Result:
Slightly lower latency
VRR still smooths most fluctuations
Occasional tearing possible, but usually minor
The key rule: don’t stack V-Sync in multiple places (driver + game + TV). That’s how you end up with extra input lag and odd frame pacing.
8. Best Settings for RTX 5090 + 4K TV (HDMI 2.1 VRR)
If you’re using a 4K HDMI 2.1 TV with your RTX 5090:
8.1 On the TV
Use an HDMI 2.1 port that supports 4K 120 Hz and VRR (check the manual)
Enable Game Mode / ALLM on that port
Turn on VRR / FreeSync / G-Sync Compatible if available
Modern gaming TVs from major brands now ship with HDMI 2.1 VRR, low input lag and 4K 120 Hz support specifically for PC and console gaming.
Disable:
Motion smoothing / interpolation
Extra noise reduction and heavy “cinema” processing
8.2 On the PC
Windows: 3840×2160 @ 120 Hz in Display settings
NVIDIA Control Panel:
4K 120 Hz selected in Change resolution
G-Sync enabled for that display (many TVs are G-Sync Compatible)
Then use Option A or B from above (VRR + V-Sync pattern + FPS cap) depending on whether you prioritise smoothness or raw responsiveness.
9. Trouble Signs and How to Fix Them
9.1 VRR isn’t working / option is greyed out
Check:
Monitor/TV OSD: Adaptive-Sync / FreeSync / VRR must be enabled there first
DisplayPort mode: Some displays default to DP 1.1; switch to DP 1.2+
Cable: use a proper DP 1.4+ or Ultra High Speed HDMI 2.1
Driver: make sure you’re on a current NVIDIA Game Ready driver
9.2 Flicker, black flashes or weird brightness shifts
Likely causes:
A flaky VRR implementation on the display
Running at the edges of the VRR range
Aggressive TV processing fighting VRR
Try:
Updating the TV/monitor firmware (many vendors refine VRR post-launch)
Narrowing the FPS range by setting a tighter FPS cap
Disabling any remaining “dynamic contrast” or brightness features
9.3 Bad input lag even with VRR
Check for stacked V-Sync:
Turn V-Sync off in-game if you’re controlling it in the driver
Make sure the TV doesn’t have its own separate V-Sync/smoothing layer enabled
Verify Game Mode is on (especially on TVs)
Then, if your display and game support it, enable NVIDIA Reflex to cut system latency further.