“System Interrupts” at 25% CPU is one of the most misunderstood Task Manager readings. It’s not a virus, it’s not a process you can kill, and reinstalling Windows rarely fixes it. It’s your hardware — or more precisely, a driver talking to your hardware — generating an interrupt storm: thousands of hardware events per second that the CPU must stop and handle, each one stealing a slice of time.

The fix is detective work with the right tools. We measure DPC latency, identify the offending driver, and fix that driver or device. It’s precise, and when you find it, the relief is immediate.

Why this happens

  • Buggy storage driver — the most common 24H2 cause; bad SATA/NVMe drivers generate interrupt storms on every I/O.
  • Failing hardware — a dying drive, bad USB device, or flaky network card retries operations endlessly.
  • Network driver issues — Wi-Fi drivers with power-management bugs generate storms, especially on wake.
  • USB device misbehaving — a faulty USB device (or hub) spamming the controller with events.
  • Audio driver DPC latency — bad audio drivers are the classic cause of DPC spikes and stuttering.
  • BIOS/firmware bugs — incorrect ACPI tables or timer configuration after updates.
  • 24H2 driver interface changes — old drivers interacting badly with new kernel timing.

How to fix it

Work through these in order — diagnose first, then act.

Fix 1: Measure DPC latency with LatencyMon

Confirm it’s a DPC/interrupt problem and identify the worst driver.

Steps:

  1. Download LatencyMon (Resplendence, free) and run it as administrator.
  2. Click Start and let it monitor for 5–10 minutes during normal use.
  3. Check the Main tab — if it reports “your system appears to be having trouble handling real-time audio,” you have a DPC problem.
  4. Go to the Drivers tab, sort by “DPC count” and “Highest execution” — the top drivers are your suspects.
  5. Note the driver filenames (e.g., storport.sys, ndis.sys, HDAudBus.sys) — they map to subsystems you’ll fix next.

Fix 2: Update the suspect drivers

Target the subsystem LatencyMon identified — don’t shotgun-update everything.

Steps:

  1. Storage (storport.sys, iaStor*): update Intel RST/chipset storage drivers from your laptop manufacturer’s site.
  2. Network (ndis.sys, tcpip.sys, Wi-Fi driver names): update Wi-Fi and Ethernet drivers; Intel wireless users should use Intel’s driver tool .
  3. Audio (HDAudBus.sys, portcls.sys, Realtek names): update the audio driver from the manufacturer.
  4. USB (usbport.sys, usbxhci.sys): update chipset drivers, which include USB controller drivers.
  5. Restart after each update and re-run LatencyMon to verify improvement.

Fix 3: Unplug USB devices to isolate hardware

A single bad USB device can generate an interrupt storm that looks like a system-wide problem.

Steps:

  1. Unplug ALL USB devices except essentials (keep just the internal keyboard/trackpad).
  2. Watch System Interrupts in Task Manager for 2–3 minutes.
  3. If CPU drops, plug devices back one at a time, waiting 2 minutes between each, until the culprit reappears.
  4. Common offenders: failing external drives, cheap USB hubs, old webcams, USB audio devices.
  5. Replace or stop using the offending device. Also try different USB ports — a damaged port itself can be the source.

Fix 4: Disable and re-enable suspect devices in Device Manager

Isolate internal devices the same way.

Steps:

  1. Open Device Manager and expand each category.
  2. Temporarily disable non-essential devices one at a time: SD card readers, fingerprint readers, secondary cameras, Bluetooth (if unused), infrared devices.
  3. After each disable, watch System Interrupts for 2 minutes.
  4. If disabling a device fixes it: update its driver; if no update helps, leave it disabled or replace the hardware.
  5. Pay special attention to network adapters — disable Wi-Fi temporarily and test on Ethernet (or vice versa) to isolate.

Fix 5: Update BIOS and chipset drivers

Firmware-level interrupt routing bugs are fixed in BIOS updates more often than people expect.

Steps:

  1. Check your BIOS version (msinfo32) against the latest on your manufacturer’s support site.
  2. Install the latest chipset driver first, then the BIOS update (charger connected, uninterrupted).
  3. In BIOS setup, look for interrupt-related settings: disable unused onboard devices (serial ports, TPM if unused — though keep TPM for Windows 11 requirements).
  4. Ensure ACPI settings are at defaults — custom tweaks can cause interrupt routing issues.
  5. Re-run LatencyMon after the update to measure improvement.

Fix 6: Fix network driver power management

Wi-Fi power-save bugs are a notorious interrupt-storm source, especially after sleep/wake.

Steps:

  1. Device Manager → Network adapters → your Wi-Fi adapter → Properties → Power Management tab.
  2. Uncheck “Allow the computer to turn off this device to save power” (counterintuitive, but the power-state transitions generate storms).
  3. In the Advanced tab, disable power-saving features like “Power Saving Mode” / set “Roaming Aggressiveness” to moderate.
  4. Update the Wi-Fi driver to the latest from Intel/Realtek/Qualcomm directly if the manufacturer’s version is old.
  5. Test after a sleep/wake cycle — that’s when these bugs manifest most.

Fix 7: Check drive health

A failing drive’s retry storms show up as System Interrupts.

Steps:

  1. Run wmic diskdrive get status — must say OK.
  2. Install CrystalDiskInfo and check SMART data for reallocated sectors or CRC errors.
  3. Run chkdsk C: /f to fix file system issues that amplify I/O interrupts.
  4. If the drive shows warnings, clone to a new SSD promptly — the interrupt problem resolves with the hardware.
  5. After drive replacement, reinstall storage drivers fresh. For the kernel-side view of this problem class, our ntoskrnl.exe guide covers the overlapping driver-hunting techniques.

Fix 8: Clean-install the worst driver with driver isolation

When updating doesn’t help, the driver installation itself may be corrupt.

Steps:

  1. In Device Manager, right-click the suspect device → Uninstall device → check “Delete the driver software for this device.”
  2. Restart — Windows installs its inbox driver.
  3. Test with the inbox driver: if interrupts are gone, the manufacturer’s driver package was corrupt; reinstall it fresh from the vendor.
  4. If interrupts persist with the inbox driver, the hardware itself is likely faulty.
  5. Document your findings — if it’s a warranty-covered component (common with Wi-Fi cards and drives), you have a clear case. Microsoft’s support hub has additional interrupt troubleshooting references.

Closing

System Interrupts high CPU is always a who-done-it, and LatencyMon (Fix 1) is the detective’s magnifying glass — it turns a mysterious 25% CPU drain into a named driver you can update, reconfigure, or remove. In the 24H2 era, storage and network drivers lead the suspect list, with USB devices as the dark horse. Work the isolation steps patiently; the moment you unplug or disable the right thing, Task Manager goes quiet and you’ll know. For step-by-step brand-specific variants, our HP and Lenovo guides cover manufacturer quirks.

Frequently asked questions

What are System Interrupts in Task Manager?
‘System Interrupts’ isn’t a real process — it’s Task Manager’s label for CPU time spent handling hardware interrupts and deferred procedure calls (DPCs). Every hardware event (network packet, disk I/O, USB activity, timer tick) generates an interrupt the CPU must service. High ‘System Interrupts’ CPU means some hardware or driver is generating far too many of them.
Is high System Interrupts CPU dangerous?
It’s not dangerous to Windows itself, but it signals a real problem: faulty hardware, a buggy driver, or a misconfigured device. Sustained high interrupt CPU wastes battery, generates heat, causes audio/video stuttering (DPC latency), and steals cycles from your apps. The underlying cause — like a failing drive — can be serious, so don’t ignore it.
Can I end the System Interrupts process?
No — there’s nothing to end. System Interrupts is an accounting category, not a process you can kill. The only fix is finding and addressing the hardware or driver generating the interrupt storm. Tools like LatencyMon and Windows Performance Analyzer identify the specific driver, which you then update, reconfigure, or whose device you disable.
Why did System Interrupts spike after the 24H2 update?
Feature updates change driver interfaces and power management, which can expose latent bugs in older drivers — a driver that was quiet under 23H2 may generate interrupt storms under 24H2’s changed timing. Storage, network, and USB drivers are the usual suspects. Updating to 24H2-certified driver versions is the primary fix.