By the FlowUP team, PC gaming system builder in Genappe (Belgium) · Updated 28 September 2026
Does your game stutter, do opponents “teleport”, or does the mouse respond with a delay? All three situations are called “lag”, but they don’t have the same cause. In fact, a lagging PC isn’t always to blame. Here’s how to identify your lag in two minutes, then fix it in the order we do when we handle it in FlowUP Support.
In brief
- Display ping and FPS in-game: a ping that climbs means a connection issue; FPS that drop means a PC issue.
- Network lag: switch to an Ethernet cable and stop background downloads.
- PC lag: check that the screen is connected to the graphics card, update drivers, lower settings, and monitor temperatures.
- Input lag: disable V-Sync, enable NVIDIA Reflex or AMD Anti-Lag, and turn on the game mode of the monitor.
- Nothing helps? Run a UserDiag test and send us the link if your PC is a FlowUP.
Contents
- Network lag, PC lag or input lag: identify yours
- Network lag: high ping and an unstable connection
- My PC lags in-game: low FPS and stutters
- Input lag: when the mouse responds late
- Does the lag persist? Run a UserDiag diagnosis.
- FAQ about lag in-game
Network lag, PC lag or input lag: identify yours
Before you change anything, display two counters during a match: ping (often in the game’s display options) and frames per second (FPS), with the overlay from NVIDIA, AMD or Steam. The table below then tells you where to look.
| What you see | Type of lag | What moves | Where to look |
|---|---|---|---|
| Players teleport, your shots don’t count, the game feels smooth but “late” | Network lag | Ping rises or spikes | Connection, Wi‑Fi, downloads |
| The image stutters, freezes for a fraction of a second—even in solo play | PC lag | FPS drop | Settings, drivers, temperatures, background activity |
| Everything feels smooth, but aiming seems heavy and misaligned | Input lag | Neither ping nor FPS | V-Sync, monitor, mouse |
Ping or FPS: check which counter moves before you touch the settings.
Network lag: high ping and an unstable connection
Ping is the latency in video games: it measures the round-trip time between your PC and the game server. It’s not the bandwidth that matters here: even a very fast fibre connection can still lag if the Wi‑Fi is saturated.
- Switch to an Ethernet cable. This is the most effective fix: Wi‑Fi adds latency and spikes, especially through walls.
- Turn off anything that’s downloading. Steam or Windows updates, OneDrive, streaming on another device in the home: all of that shares your connection.
- Restart the router and the PC. Simple, but it fixes a good portion of unstable connections.
- Choose the right server. In online games, select the closest region (West Europe for France and Belgium).
- Test your line with Fast.com, also checking the displayed latency, then compare with another device.
An Ethernet cable remains the best weapon against network lag.
My PC lags in-game: low FPS and stutters
If FPS drop, the problem comes from the machine. Here are the checks we do in Support, from fastest to longest.
1. Is the screen connected to the graphics card? This is the most common mistake we see: the HDMI or DisplayPort cable plugged into the motherboard, at the top of the case, makes the games run on the CPU’s integrated graphics (or not run at all). Connect it to the graphics card’s horizontal outputs, lower down.
The monitor’s cable connects to the graphics card, not to the motherboard ports above.
2. Close background programmes. A browser with twenty tabs, recording software, launchers: open Task Manager (Ctrl + Shift + Esc) and see what’s using the CPU and memory. In Windows, you can also limit which apps are allowed to run in the background (Microsoft support).
On Windows 10, background apps are switched off one by one in the privacy settings.
3. Compare your PC to the game’s requirements. A PC below the minimum specification will lag no matter what you do. Upgrade/compare your processor, graphics card and memory, then compare them to the game page on Steam. Our guide how to evaluate my computer’s performance shows you where to find this information.
4. Update your graphics drivers. A recent driver update often fixes stuttering in new games. Everything is explained in how to update your drivers.
5. Lower the graphics settings. Start with the most demanding options: ray tracing, shadows and volumetric quality. Then enable DLSS or FSR if the game offers it.
In a demanding game like Cyberpunk 2077, ray tracing is the first setting to turn down.
6. Put Windows into performance mode. Turn on Game Mode (Settings, Games) and select the power mode “Best performance” in Settings, System, Power. On a laptop, always plug in the charger to play.
7. Monitor temperatures. A CPU or graphics card that gets too hot will throttle to protect itself, and FPS will tank after a few minutes of play. Dust, fans that are not spinning, dried thermal paste: see our guide PC that overheats and our method for cleaning your PC.
8. Free up disk space. An almost-full SSD slows down the entire system. Keep some breathing room and delete temporary files using Windows’ Storage Assistant.
If you want to go further with FPS drops, read also why my PC lags when I play a game and what the number of FPS is.
Input lag: when the mouse responds late
Input lag is the delay between your click and the action on screen. The game can display plenty of FPS and still look “smooth”. The settings that matter:
- Disable V-Sync in the game: it adds latency. If your screen has G-Sync or FreeSync, keep that adaptive sync instead.
- Enable NVIDIA Reflex or AMD Anti-Lag when the game offers it.
- Enable your screen’s game mode and use its maximum refresh rate (144 Hz or higher) in Windows display settings.
- Check the mouse: a low battery or a wireless receiver that’s too far away is enough to cause stutters.
Mouse, screen and V-Sync handle most of the input lag.
A fast screen also reduces the perceived latency: see our guide which PC monitor to choose.
To see these settings in practice, The Pikafather channel shows how to fix lag, stuttering and slowdown issues in Windows:
Does the lag persist? Run a UserDiag diagnosis.
If nothing worked, you need to take a closer look at the hardware. UserDiag is a free tool that reads your PC’s configuration (BIOS, Windows, components) and then tests the components by measuring temperatures and CPU, memory and graphics card frequencies.
- Download UserDiag from its official website and run it.
- Choose the long or extreme diagnostic: those are the ones that heat the components enough to reveal a problem.
- In the end, the report opens in your browser, with blue tips to follow.
- Keep the report link.
Choose the long or extreme diagnostic.
The report lists the problems encountered and the advice, component by component.
Is your PC a FlowUP? Send the diagnostic link to our technical team via the contact form: with this information, we find the cause much faster.
And if your PC has simply reached the end of its life, here are two setups we build at Genappe so you can game without lag:
Banger gaming PC, powered by ASUS: RTX 5060 8GB
Ryzen 5 5600, RTX 5060 8GB, 16GB DDR4, 1TB SSD and ASUS 240mm water cooling: to play in Full HD.
Velaris GeForce RTX 5070 PC 12GB
RTX 5070 12GB, Ryzen 5 7500X3D, 16GB DDR5 and 240mm water cooling for 1440p.
FAQ about lag in-game
Why is my PC lagging even though it’s powerful?
Most of the time, the screen is plugged into the motherboard instead of the graphics card, or the lag comes from the connection and not the PC. Display the ping and FPS to see which of the two is moving.
What’s the difference between lag and low FPS?
Low FPS is a PC lag: the image stutters. Network lag, on the other hand, keeps the image smooth but shifts the players’ actions, because the ping is too high or unstable.
Can Wi‑Fi cause lag in games?
Yes. Wi‑Fi adds latency and spikes, especially when you’re far from the router. An Ethernet cable remains the most reliable solution for playing online.
How can I reduce lag on a laptop?
Plug in the charger, switch Windows to “Best performance”, check that the game is actually using the dedicated graphics card, and lift the back of the laptop so it can breathe.
Will a new PC fix the lag?
Only if it’s PC lag (low FPS). Network lag will follow you to your new machine as long as the connection isn’t fixed.
