DPC Latency & Driver IRQ Conflict Analyzer

Diagnose micro-stutters and audio crackling caused by high kernel execution times in nvlddmkm.sys, storport.sys, ndis.sys, and wdf01000.sys. Get copy-paste PowerShell fixes and MSI mode instructions.

Target Threshold< 500 µsEsports Standard

LatencyMon DPC Execution Time Simulator

Drag the slider to test your LatencyMon reported highest DPC routine value (microseconds):

380 µs(0.38 ms)

100 µs (Clean)500 µs (Borderline)1000 µs (Stutter Zone)3500 µs (Critical Freeze)

Excellent (Esports Grade)

Zero risk of audio crackle or DPC frame drops. Ideal for 240Hz+ gaming.

Select Offending Driver

What is DPC Latency?

Deferred Procedure Calls (DPCs) are tasks queued by Windows hardware drivers. If one driver takes longer than 1ms to finish, the entire Windows audio and frame rendering pipeline halts, producing crackles and frame drops.

nvlddmkm.sys

NVIDIA Windows Kernel Mode Driver

Nvidia GPU graphics driver spending excessive time handling IRQ interrupts, causing frame drops and audio pop glitches in competitive games.

Reported Symptoms & Stutters

Micro-stutters during high-FPS gameplay (Valorant, CS2)
Audio crackling when moving mouse or switching windows
Sudden FPS drop from 300 to 45 for 1-2 frames

Recommended Resolution Protocols

1.Enable MSI (Message Signaled-Based Interrupts) for NVIDIA GPU using MSI Utility v3 (set interrupt priority to High).

2.Open NVIDIA Control Panel -> Manage 3D Settings -> Power Management Mode -> Set to "Prefer Maximum Performance".

3.Disable "NVIDIA High Definition Audio" in Windows Device Manager if using a USB DAC or motherboard audio.

4.Turn off PCIe Link State Power Management in Windows Power Options (Set to "Off").

One-Click PowerShell Administrator Fix

# Disable PCIe Link State Power Management in Active Power Plan
powercfg /setacvalueindex SCHEME_CURRENT SUB_PCIEXPRESS LINKSTATEOFF 0
powercfg /setactive SCHEME_CURRENT
Write-Host "PCIe ASPM Link State Power Management Disabled!" -ForegroundColor Green

💡 Run PowerShell as Administrator, paste the snippet, and press Enter to apply immediately without restart.

MSI Mode vs Line-Based Interrupts for Gaming GPUs

Line-Based Interrupts (IRQ Legacy Mode)

In legacy IRQ mode, multiple devices (like your GPU, SATA controller, and USB hub) share a single interrupt pin on the CPU. When your GPU renders a frame, it must wait for other devices to finish their IRQ routines, causing erratic frame time spikes.

Message Signaled-Based Interrupts (MSI Mode)

MSI mode bypasses hardware interrupt lines entirely by writing directly to CPU host memory. Enabling MSI mode on NVIDIA RTX and AMD Radeon graphics cards reduces driver execution latency from 1.5ms to under 0.15ms, virtually eliminating driver-induced stutters.

Frequently Asked Questions

How do I test my PC for DPC latency?

Download and run Resplendence LatencyMon. Click the green Start button, play your game for 10 minutes, then check the "Drivers" tab sorted by "Highest execution (ms)". If any driver exceeds 1.0ms, follow the specific fixes in this matrix.

Why does high DPC latency make my microphone crackle?

Audio streams require a continuous real-time buffer delivered every 5 to 10 milliseconds. If a graphics or storage driver hogs CPU core 0, the audio buffer empties (buffer underrun), resulting in an audible click, pop, or robot voice.

Is it safe to enable MSI mode on my GPU?

Yes. All modern GPUs since NVIDIA GTX 900 series and AMD RX 400 series fully support MSI mode hardware-wise. However, Windows clean installs still default some cards to legacy line interrupts. Setting MSI mode via MSI Utility v3 is standard esports optimization practice.