DPC latency stutter in games

Hi,

So i started noticing stutter (sometimes audio stutters aswell) in games since beginning of january (2021). The stutter is worst right after the game have loaded and evens out after 30 - 50 seconds or so. After that the stuttering is much less noticeable, but still present and more random. This is present in almost all games.

This is what i have tried so far:

• reinstalled windows
• tested to downgrade windows to an earlier build (20H2-19042.508)
• turned off/on v-sync/G-sync
• tested FPS cap
• Switched power plan from balanced to high performance
• turned off windows indexer
• Turned XMP1/XMP2 on/off
• reinstalled games
• started games from different drives (both SSD and nvm2)
• Tried different settings in nvidia control panel (prefer maximum performance, etc)
• updated all drivers and updates in windows
• Did one hour power stress test in OCCT to test my new PSU (Corsair RM850)
• connected GPU via 2 power cables (2x8 pin seperate cables, instead of one cable)
• tested different ram modules
• created task in task scheduler to free up windows system cache every 5 minutes (empty standby list)
• updated bios
• downgraded bios
• removed all form for monitoring sofware such as afterburner, rivatuner, HW monitor, etc
• uninstalled utility software such as Icue and Ghub
• changed DPI and refresh rate on mouse
• rolled back to earlier display drivers (451.71 and 460.89)
• game mode on/off
• hardware accelerated gpu scheduler on/off
• turned off/on ingame overlay (including xbox bar/geforce experience ect)
• disconnected mechanical HDD (even though games only run from SSD)
• turned off/on asus multicore enhancement (deafult on)
• turned off fast startup in windows

Then i came over a program called latencyMon which showed me that my system is suffering from very bad latency caused by nvidia driver

Latencymon:

Your system appears to be having trouble handling real-time audio and other tasks. You are likely to experience buffer underruns appearing as drop outs, clicks or pops. One or more DPC routines that belong to a driver running in your system appear to be executing for too long. One problem may be related to power management, disable CPU throttling settings in Control Panel and BIOS setup. Check for BIOS updates.

LatencyMon has been analyzing your system for  0:04:34  (h:mm:ss) on all processors.

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SYSTEM INFORMATION

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Computer name:                                        GAMING-CENTER

OS version:                                           Windows 10, 10.0, version 2009, build: 19042 (x64)

Hardware:                                             System Product Name, ASUS

CPU:                                                  GenuineIntel Intel(R) Core(TM) i7-9700K CPU @ 3.60GHz

Logical processors:                                   8

Processor groups:                                     1

RAM:                                                  16298 MB total

_________________________________________________________________________________________________________

CPU SPEED

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Reported CPU speed:                                   360 MHz

Note: reported execution times may be calculated based on a fixed reported CPU speed. Disable variable speed settings like Intel Speed Step and AMD Cool N Quiet in the BIOS setup for more accurate results.

_________________________________________________________________________________________________________

MEASURED INTERRUPT TO USER PROCESS LATENCIES

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The interrupt to process latency reflects the measured interval that a usermode process needed to respond to a hardware request from the moment the interrupt service routine started execution. This includes the scheduling and execution of a DPC routine, the signaling of an event and the waking up of a usermode thread from an idle wait state in response to that event.

Highest measured interrupt to process latency (µs):   10866,10

Average measured interrupt to process latency (µs):   3,313754

Highest measured interrupt to DPC latency (µs):       10825,70

Average measured interrupt to DPC latency (µs):       1,500609

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REPORTED ISRs

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Interrupt service routines are routines installed by the OS and device drivers that execute in response to a hardware interrupt signal.

Highest ISR routine execution time (µs):              310,772778

Driver with highest ISR routine execution time:       dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Highest reported total ISR routine time (%):          0,185047

Driver with highest ISR total time:                   dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Total time spent in ISRs (%)                          0,238419

ISR count (execution time <250 µs):                   426979

ISR count (execution time 250-500 µs):                0

ISR count (execution time 500-1000 µs):               2

ISR count (execution time 1000-2000 µs):              0

ISR count (execution time 2000-4000 µs):              0

ISR count (execution time >=4000 µs):                 0

_________________________________________________________________________________________________________

REPORTED DPCs

_________________________________________________________________________________________________________

DPC routines are part of the interrupt servicing dispatch mechanism and disable the possibility for a process to utilize the CPU while it is interrupted until the DPC has finished execution.

Highest DPC routine execution time (µs):              15726,577778

Driver with highest DPC routine execution time:       nvlddmkm.sys - NVIDIA Windows Kernel Mode Driver, Version 461.40 , NVIDIA Corporation

Highest reported total DPC routine time (%):          0,075542

Driver with highest DPC total execution time:         dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Total time spent in DPCs (%)                          0,181608

DPC count (execution time <250 µs):                   597512

DPC count (execution time 250-500 µs):                0

DPC count (execution time 500-10000 µs):              11

DPC count (execution time 1000-2000 µs):              7

DPC count (execution time 2000-4000 µs):              0

DPC count (execution time >=4000 µs):                 1

Every bar in latencymon was red. I would paste a screenshot from latency monitor if it was possible. (I have more information from latencymon if needed. I suspect that there is a problem with drivers from nvidia, but im not sure.

My specs:

Display driver: 461.51 (latest hotfix)

CPU: 9700k (no overclock) (max temp in games 65c)
GPU: Asus 2080S (no overclock (max temp in games 72c)
RAM: 16gb 3200 mhz corsair venegance
PSU: corsair RM850 
Motherboard: Asus strix Z-390f 
Windows 10 pro 20H2 Do you have any tips? :)