It’s one of the most common questions on gaming subreddits: should I turn off my antivirus when gaming? The fear is real — background processes eating CPU, scans kicking in mid-match, FPS drops during intense scenes. The honest answer is more nuanced than yes or no.
Short Answer: A well-configured antivirus on a modern gaming PC causes no noticeable FPS impact. The problems come from scheduled full scans running during gameplay and real-time scanning of your games folder. Fix both with Gaming Mode and a scan exclusion for your games directory — and never fully disable antivirus while gaming.
What antivirus actually does in the background
When you’re gaming, your antivirus is doing two things: real-time file scanning (intercepting every file read/write to check for threats) and periodic scheduled scans (full system scans you probably set up and forgot). The first is usually harmless on modern hardware. The second is the real culprit.
Real-time scanning works by hooking into the file system. Every time your game loads a texture, spawns an asset, or writes a save file, the antivirus intercepts it briefly. On NVMe SSDs this interception is microseconds. On older HDDs, where read speeds are 50–150 MB/s versus 3,000–7,000 MB/s on NVMe, the cumulative overhead can cause noticeable stutter in games that stream assets heavily — open-world games, level loading, cutscene transitions.
The real FPS killer: scheduled scans
If you’ve ever had a game suddenly stutter or your CPU shoot to 80% mid-session for no apparent reason, a background scan kicking in is the most likely cause. Full system scans are CPU and disk intensive. Running one while gaming is the equivalent of running a benchmark while playing.
The fix is Gaming Mode — available in Bitdefender, Norton, ESET, Kaspersky, and most premium antivirus products. It detects full-screen applications and defers all scheduled tasks and non-critical notifications until you’re done playing.
Real benchmark numbers
Independent tests from AV-Comparatives’ Performance Test consistently show that the performance impact of top antivirus products during gaming is 1–3% on average FPS — statistically within margin of error on a modern gaming PC. The outliers are products running active full scans simultaneously, where the impact jumps to 15–25%. The conclusion: it’s not the antivirus itself, it’s poorly timed scans.
- Bitdefender: 0–2% FPS impact with Game Mode on
- Malwarebytes Premium: <1% (minimal background activity by design)
- ESET NOD32: 1–2% (light footprint)
- Windows Defender: 2–5% (no dedicated gaming mode)
- Norton 360: 2–4% with Silent Mode on; higher without
The three fixes that eliminate antivirus lag while gaming
Fix 1 — Enable Gaming / Silent Mode
Open your antivirus settings and enable Gaming Mode, Silent Mode, or Do Not Disturb mode. This defers scans and suppresses notifications automatically when it detects a full-screen application. You don’t need to do anything else — it activates when your game starts and deactivates when you exit.
Fix 2 — Exclude your games folder from real-time scanning
Add your games directory (typically C:Program Files (x86)Steamsteamapps or wherever you install games) as a scan exclusion in your antivirus. This tells the real-time scanner to skip those files entirely. The tradeoff: newly downloaded game files won’t be scanned as they arrive. Mitigate this by running a manual on-demand scan after installing new games, then leaving the exclusion in place.
How to add exclusion: Antivirus Settings → Exclusions → Add folder → Select your Steam/Epic/games directory.
Fix 3 — Schedule full scans for off-hours
Set your scheduled full system scan to run at 3AM, or when your PC is idle, or right after startup before you open any games. Most antivirus products let you set a custom scan schedule. This ensures the heavy CPU and disk work happens when you’re not using the machine.
Optimal antivirus gaming config:
Gaming Mode → On | Games folder → Excluded from real-time scan | Scheduled scan → 3AM or on idle
Warning: Turning off antivirus completely while gaming is not a good trade. Gamers are targeted by malware through mod downloads, fake cheat software, and phishing overlays. The correct solution is Gaming Mode — it gets you 99% of the performance benefit without removing protection.
Should you switch antivirus if yours impacts gaming?
If you’ve applied all three fixes and still notice performance issues, your current antivirus may genuinely be poorly optimised for gaming. Bitdefender and Malwarebytes consistently score the lowest in performance impact tests. See: Best antivirus for gaming PC for a full comparison.
Checklist:
- ✅ Gaming Mode / Silent Mode enabled
- ✅ Games folder added to scan exclusions
- ✅ Scheduled scans set to off-hours
- ✅ Never fully disable antivirus — use Gaming Mode instead
- ✅ Run manual scan after each new game install
FAQ
Does Windows Defender affect gaming FPS?
Windows Defender has a 2–5% average impact in benchmarks — slightly higher than dedicated gaming antivirus products because it lacks an automatic gaming mode. You can mitigate this by adding your games folder as an exclusion in Windows Security → Virus & Threat Protection → Exclusions.
Why does my CPU spike to 100% while gaming?
If your CPU spikes suddenly mid-game, check Task Manager for your antivirus process. If it shows high CPU, a background scan triggered. Enable Gaming Mode to prevent this, or reschedule your scans for off-hours.
Does excluding my games folder from antivirus make me vulnerable?
Slightly — newly downloaded game files won’t be auto-scanned in real time. Run a manual on-demand scan after installing each game to compensate. The trade-off is worth it for the performance gain in large games that stream many files.
Related: Best antivirus for gaming PC | Best password manager for gamers | Best VPN for gaming
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