Game Error Fortnite

Fortnite High CPU Usage by ntoskrnl.exe (Easy Anti-Cheat) - Fix Guide

📅 Published: 2026-02-05 🔄 Updated: 2026-02-05 👥 Reports: 6 ⚡ Severity: 🟢 Low

🎯 Quick Answer

Enable Virtualization-Based Security (VBS) and Memory Integrity in Windows Security to resolve the high ntoskrnl.exe CPU usage caused by Easy Anti-Cheat.

SECTION 1: OVERVIEW

This error manifests as abnormally high CPU utilization by the Windows kernel process, ntoskrnl.exe, specifically during the operation of games protected by Easy Anti-Cheat (EAC), including Fortnite. The process consumes 20-30% of system CPU resources, which is a significant deviation from normal background operation. This issue affects the Windows platform exclusively, as EAC is a Windows-specific service. The problem occurs across multiple game versions where EAC is implemented and is not tied to a specific Fortnite update. This is a common issue reported on systems with specific hardware and software configurations. The severity is high, as the resource contention directly causes performance degradation, resulting in consistent in-game stuttering and FPS drops. The error does not generate a user-facing error code; the primary indicator is sustained high CPU usage observed in Task Manager and correlated gameplay disruption.

SECTION 2: SYMPTOMS

The ntoskrnl.exe system process exhibits sustained CPU usage between 20% and 30% as monitored in Windows Task Manager or Resource Monitor. This elevated usage initiates upon launching Fortnite or any other Easy Anti-Cheat-protected title and persists in the game lobby and during active gameplay. The high kernel-level CPU consumption creates a systemic resource bottleneck. This bottleneck results in inconsistent frame delivery (stuttering) and a measurable reduction in frames per second (FPS) during gameplay. The application may also exhibit increased input latency. The issue terminates only when the game process and its associated EAC service are fully closed.

SECTION 3: COMMON CAUSES

Category: Configuration Error Specific technical explanation: Virtualization-Based Security (VBS) and its Core Isolation Memory Integrity feature are disabled in Windows Security. Easy Anti-Cheat requires specific Windows security features to function optimally with certain CPU architectures. When these features are absent, EAC employs less efficient fallback mechanisms that cause excessive kernel calls, resulting in high ntoskrnl.exe CPU overhead. Category: Software Conflict Specific technical explanation: Outdated, corrupted, or incompatible system drivers, particularly for chipset, storage (NVMe/SSD), or peripheral controllers. Incompatible drivers can cause inefficient hardware communication paths that the Windows kernel must manage, exacerbating the load from anti-cheat software. Category: Game Bug / Anti-Cheat Bug Specific technical explanation: A known compatibility issue between specific versions of the Easy Anti-Cheat service and Windows kernel-level memory management routines on systems with hybrid CPU architectures (Intel 12th/13th/14th Gen or AMD Ryzen with 3D V-Cache). The anti-cheat software performs excessive privilege-level context switches. Category: Configuration Error Specific technical explanation: Incorrect or suboptimal power plan settings in Windows, particularly a plan that disables core parking or uses aggressive performance states. This conflicts with the scheduling requirements of kernel threads spawned by the anti-cheat. Category: Software Conflict Specific technical explanation: Conflicting security or monitoring software, such as outdated RGB lighting control utilities (e.g., ASUS Armoury Crate, NZXT CAM), system monitoring tools, or legacy antivirus suites. These applications hook into kernel operations, creating contention with EAC's kernel-mode driver. Category: Hardware Issue Specific technical explanation: System firmware (BIOS/UEFI) is outdated and contains microcode that mismanages CPU threads under the specific load pattern generated by kernel-level anti-cheat operations. This is prevalent on newer CPU architectures. Category: Configuration Error Specific technical explanation: The Easy Anti-Cheat service installation for Fortnite is corrupted or has incorrect file permissions, causing it to fail initial handshake protocols and enter a high-polling state.

SECTION 4: SOLUTIONS

Solution 1: Enable Virtualization-Based Security and Memory Integrity

Difficulty: Medium Time Required: 10 minutes Success Rate: High Prerequisites: Windows 10/11 Pro, Education, or Enterprise; CPU with SLAT support; Admin access required. Steps:

Open Windows Security by searching for it in the Start Menu.
Select Device security.
Under Core isolation, click Core isolation details.
Toggle the switch for Memory integrity to On. If the option is grayed out, virtualization may be disabled in BIOS/UEFI.
If prompted, restart your system. After reboot, Windows Security may indicate additional steps are needed; follow them.
Verify the setting is active. Return to Device security > Core isolation details. The Memory integrity toggle should show On.
Launch Fortnite and monitor ntoskrnl.exe CPU usage in Task Manager (Details tab).

Technical Explanation: Enabling Memory Integrity forces all kernel-mode drivers to run in a secure, isolated virtual environment using hardware virtualization. This provides the specific secure context Easy Anti-Ceat expects on modern systems, eliminating its fallback to inefficient, high-frequency kernel polling mechanisms. Verification: ntoskrnl.exe CPU usage returns to typical background levels (0-2% at idle, minor spikes during gameplay). Fortnite gameplay exhibits no stuttering and stable FPS.

Solution 2: Update System Drivers and BIOS/UEFI Firmware

Difficulty: Advanced Time Required: 20-30 minutes Success Rate: Medium Prerequisites: Admin access, ability to download files from motherboard manufacturer's website. Steps:

Identify your motherboard model (via System Information, Command Prompt wmic baseboard get product,Manufacturer, or physically).
Visit the support website for your motherboard manufacturer (e.g., ASUS, Gigabyte, MSI, ASRock).
Download the latest stable BIOS/UEFI firmware update and the latest chipset driver package for your specific motherboard model and Windows version.
Follow the manufacturer's precise instructions to update the BIOS/UEFI. This typically involves extracting a file to a USB drive and using the BIOS flash utility.
After the BIOS update completes, boot into Windows. Install the downloaded chipset drivers, restarting if prompted.
Use Windows Update to check for optional driver updates, particularly for "System devices" like Intel Management Engine Interface or PCI Express controllers.

Technical Explanation: Newer CPU architectures require updated microcode (delivered via BIOS) and chipset drivers to correctly handle thread scheduling and kernel security calls from software like EAC. Outdated firmware can cause excessive kernel overhead. Verification: System stability is maintained. Check BIOS version in System Information (msinfo32) and driver dates in Device Manager to confirm updates applied.

Solution 3: Perform a Clean Reinstallation of Easy Anti-Cheat

Difficulty: Easy Time Required: 5 minutes Success Rate: Medium Prerequisites: Fortnite must be closed. Steps:

Navigate to the Easy Anti-Cheat installation directory for Fortnite: C:\Program Files\Epic Games\Fortnite\FortniteGame\Binaries\Win64\EasyAntiCheat.
Locate and run the EasyAntiCheat_Setup.exe file as Administrator (right-click > Run as administrator).
In the setup dialog, ensure Fortnite is selected in the dropdown menu.
Click the Repair Service button. Wait for the process to complete.
If the issue persists, return to the setup utility, select Fortnite again, and click Uninstall Service. Restart your computer.
After restarting, run EasyAntiCheat_Setup.exe as Administrator once more and click Install Service.

Technical Explanation: This process replaces corrupted or incorrectly configured EAC service files and registry entries with a fresh installation, ensuring proper integration with the Windows kernel and game client. Verification: The EAC service starts without error when Fortnite launches. Monitor CPU usage post-reinstallation.

Solution 4: Configure Windows Power Plan for High Performance

Difficulty: Easy Time Required: 3 minutes Success Rate: Low-Medium Prerequisites: None. Steps:

Open the Windows Control Panel and select Hardware and Sound > Power Options.
Select the High performance power plan. If it is not visible, click Show additional plans.
If necessary, create a custom plan: Click Create a power plan on the left, choose High performance, name it, and click Next. Set all dropdowns to Maximum performance.
Click Change plan settings next to the selected High Performance plan, then Change advanced power settings.
In the advanced settings window, expand Processor power management.
Set Minimum processor state to 100%.
Set Maximum processor state to 100%.
Expand PCI Express > Link State Power Management and set it to Off.
Click Apply and OK. Restart the system.

Technical Explanation: Preventing CPU core parking and aggressive power state transitions reduces latency in kernel thread scheduling, which can alleviate contention caused by the anti-cheat's real-time scanning threads. Verification: The selected power plan is active. System responsiveness may improve, and kernel CPU spikes may reduce in frequency.

Solution 5: Disable Conflicting Third-Party Software

Difficulty: Medium Time Required: 10 minutes Success Rate: Medium Prerequisites: Admin access may be required to uninstall software. Steps:

Open Task Manager (Ctrl+Shift+Esc) and review the Startup tab for non-essential applications like RGB controllers, hardware monitors, or legacy game boosters.
Right-click and Disable these applications from starting automatically.
Restart the computer.
After restarting, before launching any other software, launch Fortnite directly and test for the issue.
If the issue is resolved, systematically re-enable startup items to identify the conflict.
Permanently uninstall conflicting software via Settings > Apps > Installed apps. Common culprits include outdated versions of: ASUS Armoury Crate, MSI Dragon Center, Corsair iCUE (update to latest), NZXT CAM, or Discord overlay.

Technical Explanation: These applications often install kernel-mode drivers that hook into the same system calls as Easy Anti-Cheat. The conflict generates excessive kernel-level interrupts, manifesting as high ntoskrnl.exe CPU load. Verification: With conflicting software disabled, ntoskrnl.exe CPU usage normalizes during Fortnite execution.

Solution 6: Verify Windows System File Integrity

Difficulty: Easy Time Required: 10-15 minutes Success Rate: Low Prerequisites: Admin access, internet connection for Windows component downloads. Steps:

Open Command Prompt as Administrator (search for cmd, right-click > Run as administrator).
Execute the System File Checker command: sfc /scannow. Allow the scan to complete (100%).
If SFC reports corrupted files and repaired them, restart your computer.
After restart, open an Admin Command Prompt again and run the DISM tool to repair the Windows image: DISM /Online /Cleanup-Image /RestoreHealth.
Allow this process to complete; it may take several minutes and requires an internet connection.
Restart the computer once more after DISM completes.

Technical Explanation: Corrupted Windows kernel components or system libraries can cause abnormal behavior when under load from kernel-mode drivers like EAC. SFC and DISM replace incorrect versions with authentic Microsoft files. Verification: The commands complete without reporting unreparable corruption. System stability is unchanged or improved.

SECTION 5: PREVENTION

Maintain current system firmware and driver versions, prioritizing chipset and storage controller updates from manufacturer sources. Configure Windows Update to install updates automatically, including optional driver updates. Avoid installing unnecessary system utility software that operates at the kernel level, such as performance boosters or outdated hardware control suites. Periodically verify the integrity of the Easy Anti-Cheat installation via its setup utility. After major Windows feature updates, re-check that Virtualization-Based Security and Memory Integrity remain enabled in Windows Security, as updates can reset these features.

SECTION 6: WHEN TO CONTACT SUPPORT

Contact Epic Games Support if all documented solutions fail and the high ntoskrnl.exe CPU usage persists exclusively with Fortnite. Before contacting support, gather the following diagnostic information: a full system specification report from dxdiag, a performance log from Windows Performance Recorder during the issue, and the Easy Anti-Cheat service logs located in C:\Program Files\Epic Games\Fortnite\FortniteGame\Binaries\Win64\EasyAntiCheat\Logs. Provide a clear timeline of the issue and the specific troubleshooting steps already executed. Official support channels are accessible via the Epic Games Help Center website.