Question What's causing High DPC latency on my PC ?

[FrustratedWin11Gamer]

Hi, I have recently built a new PC, but it's unplayable due to high DPC latency. I've had this for over a month now and I've done everything:

• Updated latest Bios
• In Bios I've disabled onboard graphics, sound, wifi, serial connector, network, stack and power saving (PSS)
• Drivers - I've updated AM5 chipset drivers for motherboard from AMD. Updated LAN drivers from Realtek, updated latest Nvidia drivers using NVClean.
• I've done 6 clean reinstalls of windows 11 and I've tried many other "fixes" from every corner of the internet, (max power, turn off virtualisation, used MSI app, etc), all to no avail.

Specs:
CPU - AMD 7700X
Motherboard - ASUS TUF B650 Plus
Memory - Kingston FURY Beast 32GB (2x16GB) 6000MT/s DDR5 CL40
GPU - Palit Blackrock 4080
SSD - 2TB Samsung 990 Pro + older 1TB Samsumg SATA drive
PSU - Corsair RM850

Some people have talked about using older Nvidia drivers for lower DPC latency, but since the graphics card is new I coan't roll back to drivers that pre-exist it. Please can someone help.

 

[Fix_that_Glitch]

Have you tried this app? Resplendence Software - LatencyMon: suitability checker for real-time audio and other tasks

 

[Fix_that_Glitch]

Is AMD cool and quiet enabled in bios? (Try disabling if so)

 

[FrustratedWin11Gamer]

I have PSS turned off in Bios, which is the closest thing to cool and quiet in my ASUS TUF B650 Plus motherboard.

Yes I use Latency Mon too. Here's the report

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CONCLUSION
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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 0:07:30 (h🇲🇲ss) on all processors.


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SYSTEM INFORMATION
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Computer name: DANSPC
OS version: Windows 10, 10.0, version 2009, build: 22621 (x64)
Hardware: System Product Name, ASUS
CPU: AuthenticAMD AMD Ryzen 7 7700X 8-Core Processor
Logical processors: 16
Processor groups: 1
RAM: 32499 MB total


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CPU SPEED
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Reported CPU speed: 4492 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.


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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): 2617.30
Average measured interrupt to process latency (µs): 4.476234

Highest measured interrupt to DPC latency (µs): 2615.20
Average measured interrupt to DPC latency (µs): 1.525184


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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): 969.864203
Driver with highest ISR routine execution time: Wdf01000.sys - Kernel Mode Driver Framework Runtime, Microsoft Corporation

Highest reported total ISR routine time (%): 0.001043
Driver with highest ISR total time: Wdf01000.sys - Kernel Mode Driver Framework Runtime, Microsoft Corporation

Total time spent in ISRs (%) 0.001048

ISR count (execution time <250 µs): 71037
ISR count (execution time 250-500 µs): 0
ISR count (execution time 500-1000 µs): 1
ISR count (execution time 1000-2000 µs): 0
ISR count (execution time 2000-4000 µs): 0
ISR count (execution time >=4000 µs): 0


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REPORTED DPCs
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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): 5274.306545
Driver with highest DPC routine execution time: nvlddmkm.sys - NVIDIA Windows Kernel Mode Driver, Version 528.49 , NVIDIA Corporation

Highest reported total DPC routine time (%): 0.059878
Driver with highest DPC total execution time: dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Total time spent in DPCs (%) 0.137756

DPC count (execution time <250 µs): 1144197
DPC count (execution time 250-500 µs): 0
DPC count (execution time 500-10000 µs): 140
DPC count (execution time 1000-2000 µs): 5
DPC count (execution time 2000-4000 µs): 50
DPC count (execution time >=4000 µs): 1


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REPORTED HARD PAGEFAULTS
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Hard pagefaults are events that get triggered by making use of virtual memory that is not resident in RAM but backed by a memory mapped file on disk. The process of resolving the hard pagefault requires reading in the memory from disk while the process is interrupted and blocked from execution.

NOTE: some processes were hit by hard pagefaults. If these were programs producing audio, they are likely to interrupt the audio stream resulting in dropouts, clicks and pops. Check the Processes tab to see which programs were hit.

Process with highest pagefault count: hogwartslegacy.exe

Total number of hard pagefaults 32244
Hard pagefault count of hardest hit process: 14036
Number of processes hit: 74


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PER CPU DATA
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CPU 0 Interrupt cycle time (s): 5.276311
CPU 0 ISR highest execution time (µs): 969.864203
CPU 0 ISR total execution time (s): 0.051909
CPU 0 ISR count: 36765
CPU 0 DPC highest execution time (µs): 2699.989982
CPU 0 DPC total execution time (s): 0.763088
CPU 0 DPC count: 105162
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CPU 1 Interrupt cycle time (s): 1.171838
CPU 1 ISR highest execution time (µs): 0.0
CPU 1 ISR total execution time (s): 0.0
CPU 1 ISR count: 0
CPU 1 DPC highest execution time (µs): 2608.958148
CPU 1 DPC total execution time (s): 0.033052
CPU 1 DPC count: 12170
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CPU 2 Interrupt cycle time (s): 1.507943
CPU 2 ISR highest execution time (µs): 0.0
CPU 2 ISR total execution time (s): 0.0
CPU 2 ISR count: 0
CPU 2 DPC highest execution time (µs): 2613.305877
CPU 2 DPC total execution time (s): 0.062538
CPU 2 DPC count: 36461
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CPU 3 Interrupt cycle time (s): 1.280749
CPU 3 ISR highest execution time (µs): 0.0
CPU 3 ISR total execution time (s): 0.0
CPU 3 ISR count: 0
CPU 3 DPC highest execution time (µs): 58.313669
CPU 3 DPC total execution time (s): 0.007977
CPU 3 DPC count: 3735
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CPU 4 Interrupt cycle time (s): 1.417014
CPU 4 ISR highest execution time (µs): 0.0
CPU 4 ISR total execution time (s): 0.0
CPU 4 ISR count: 0
CPU 4 DPC highest execution time (µs): 178.547418
CPU 4 DPC total execution time (s): 0.055766
CPU 4 DPC count: 23127
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CPU 5 Interrupt cycle time (s): 25.299660
CPU 5 ISR highest execution time (µs): 0.0
CPU 5 ISR total execution time (s): 0.0
CPU 5 ISR count: 0
CPU 5 DPC highest execution time (µs): 5274.306545
CPU 5 DPC total execution time (s): 8.431143
CPU 5 DPC count: 783738
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CPU 6 Interrupt cycle time (s): 1.515385
CPU 6 ISR highest execution time (µs): 0.0
CPU 6 ISR total execution time (s): 0.0
CPU 6 ISR count: 0
CPU 6 DPC highest execution time (µs): 148.273598
CPU 6 DPC total execution time (s): 0.061383
CPU 6 DPC count: 26379
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CPU 7 Interrupt cycle time (s): 1.307842
CPU 7 ISR highest execution time (µs): 0.0
CPU 7 ISR total execution time (s): 0.0
CPU 7 ISR count: 0
CPU 7 DPC highest execution time (µs): 2611.302315
CPU 7 DPC total execution time (s): 0.029465
CPU 7 DPC count: 9170
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CPU 8 Interrupt cycle time (s): 1.577022
CPU 8 ISR highest execution time (µs): 0.0
CPU 8 ISR total execution time (s): 0.0
CPU 8 ISR count: 0
CPU 8 DPC highest execution time (µs): 801.815450
CPU 8 DPC total execution time (s): 0.058171
CPU 8 DPC count: 22818
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CPU 9 Interrupt cycle time (s): 1.182581
CPU 9 ISR highest execution time (µs): 0.0
CPU 9 ISR total execution time (s): 0.0
CPU 9 ISR count: 0
CPU 9 DPC highest execution time (µs): 94.157391
CPU 9 DPC total execution time (s): 0.029198
CPU 9 DPC count: 8452
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CPU 10 Interrupt cycle time (s): 1.589439
CPU 10 ISR highest execution time (µs): 0.0
CPU 10 ISR total execution time (s): 0.0
CPU 10 ISR count: 0
CPU 10 DPC highest execution time (µs): 92.424310
CPU 10 DPC total execution time (s): 0.060544
CPU 10 DPC count: 22749
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CPU 11 Interrupt cycle time (s): 1.333131
CPU 11 ISR highest execution time (µs): 0.0
CPU 11 ISR total execution time (s): 0.0
CPU 11 ISR count: 0
CPU 11 DPC highest execution time (µs): 2607.886242
CPU 11 DPC total execution time (s): 0.056493
CPU 11 DPC count: 25142
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CPU 12 Interrupt cycle time (s): 1.760355
CPU 12 ISR highest execution time (µs): 8.875779
CPU 12 ISR total execution time (s): 0.017399
CPU 12 ISR count: 25458
CPU 12 DPC highest execution time (µs): 2613.886910
CPU 12 DPC total execution time (s): 0.082205
CPU 12 DPC count: 27882
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CPU 13 Interrupt cycle time (s): 1.284740
CPU 13 ISR highest execution time (µs): 16.349065
CPU 13 ISR total execution time (s): 0.003095
CPU 13 ISR count: 4483
CPU 13 DPC highest execution time (µs): 100.719056
CPU 13 DPC total execution time (s): 0.026965
CPU 13 DPC count: 6973
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CPU 14 Interrupt cycle time (s): 1.761489
CPU 14 ISR highest execution time (µs): 8.254675
CPU 14 ISR total execution time (s): 0.002331
CPU 14 ISR count: 3252
CPU 14 DPC highest execution time (µs): 2605.552093
CPU 14 DPC total execution time (s): 0.11140
CPU 14 DPC count: 23553
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CPU 15 Interrupt cycle time (s): 1.350158
CPU 15 ISR highest execution time (µs): 7.072573
CPU 15 ISR total execution time (s): 0.000815
CPU 15 ISR count: 1080
CPU 15 DPC highest execution time (µs): 1503.84350
CPU 15 DPC total execution time (s): 0.060410
CPU 15 DPC count: 6882
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[Fix_that_Glitch]

You said you have tried several installations of Win 11 but your system is reporting as Windows 10? You can try under device manager, system devices, High precision timer-disable. Try unplugging your hd. Try uninstalling your sound drivers and let windows replace the files automatically. Are you using high performance in Windows power settings? If you have Armoury crate installed uninstall it. Use DDU uninstaller to completely remove any loose/installed Drivers. Then install fresh drivers without NVCLEAN. https://www.guru3d.com/files-details/display-driver-uninstaller-download.html Use only drivers from the Asus support page (except for GPU drivers). If you used any other site for drivers erase those and install from Asus support page. TUF GAMING B650-PLUS｜Motherboards｜ASUS Global

 

[FrustratedWin11Gamer]

OK, so lots to do here and none of it helped

1. You said you have tried several installations of Win 11 but your system is reporting as Windows 10? -- Yes Windows build: 22621 is in fact the windows 11 build released 5 days ago. That LatencyMon calls it windows 10, I can't answer for that.
2. You can try under device manager, system devices, High precision timer-disable. -- Already did that
3. Try unplugging your hd. - HD? Please, I haven't had an HD since 2014. I've an M.2 SSD and a SATA one, and yes before you ask I've diasabled the SATA one in the past to see if it helped. It didn't
4. Try uninstalling your sound drivers and let windows replace the files automatically. -- I disabled onboard sound, but I have a EPOS GSD 670 headset where the dongle is the audio driver. It is on windows drivers already. I haave installed the software in the past but it didn't have updated drivers. I've also disabled the sound from the Nvidia 4080 in case there was any conflict. It didn't help.
5. Are you using high performance in Windows power settings? -- Of course. I've also made changes in registry to set processor parking cores to min 100% and of courese processor state to min 100%. I've also set the GPU to performance in Nvidia Bios. I've set USB suspending to disabled. etc.
6. If you have Armoury crate installed uninstall it. -- I'm not
7. Then install fresh drivers without NVCLEAN. https://www.guru3d.com/files-details/display-driver-uninstaller-download.html Use only drivers from the Asus support page (except for GPU drivers). -- I did this and it was a complete disaster. I had previously an NVclean install of Nvidia drivers with MSI and specified it to use processor 6 on high priority (anything bbut processor 0 to minimise conflicts). Of course with a basic install none of that is set. My LatencyMon spiked to 2.9ms execution lag within 10 seconds of turning it on. Hence this is a massive step backwards. So I'll have to reverse that.
8. If you used any other site for drivers erase those and install from Asus support page. TUF GAMING B650-PLUS｜Motherboards｜ASUS Global -- I've done 6 clean windows installs. I've done it with different Bios settings. I've done drivers from Asus site. I've done drivers directly from AMD and Realtek directly (which are more recent tthan the ASUS ones), I've done drivers using Armoury crate. None of these make any difference.

While I really appreciate the support, I've had this issue for 7 weeks and I've trawled the internet for solutions and tried a hundred different tweaks, changes, bios settings, drivers from different places, registry changes, disabling programs and services, etc, etc. I've also replaced the motherboard and the memory. So far nothing has worked. I really need something a little more tailored. If I need to run any report or diagnostic program please let me know, but there is no point taking shots in the dark as I've been doing a lot of that and hit nothing.

I'm half thinking, could it be a fault with the GPU, but how would I test for that? The infuriating thing here is not being able to isolate the cause of the issue.

 

[FrustratedWin11Gamer]

Could it be an interupt conflict issue I'm dealling with? Certainly setting MSI for the GPU and pointing to a specified processor helps but doesn't fully aleviate the issue. So that at least hints at the cause. If so what can I do?

Also before anyone says I've already used the MSI utility app, set everything to MSI, put GPU and network card on high, everything else on low. Didn't fix the issue. ..

 

[adaco]

Any luck on fixing this issue? I've also looked everywhere and nothing has worked.

 

[Jordakn]

I've also been having this problem for ages, and can't figure out a fix. Far as I can tell, the problem lies with Nvidia's drivers for the 3000/4000 series cards, and how they interact with the Windows kernel. No "fixes" work because, unless you don't mind not using your monitor, there is nothing the consumer can do.

I rolled back to v512.95, and it seems to have helped a tiny bit, but not enough to totally fix the issue. Consistent DPC latency spikes dropped from 2ms+ to only 1ms+, which is apparently still enough to cause problems.

 

[BotanGohan]

I have had a similar issue with high DPC latency. I believe the issue stems from some conflicts on PCIe interrupts in PCIE 4.0 modes. On my machine, I have interrupt conflicts on 0x00 (System clock and High precision timer), and 0x55 (PCIe bridge and Nvidia HD Audio).

Of all the fixes I have attempted, the one that has lasted the longest is this:

1. Set the GPU PCIe slot to 16x3.0 in the ASUS bios

I have tried many fixes including:

1. Disabling High Precision Timer
2. Setting GPU and HD Audio to MSI mode
3. Manually setting interrupt affinity for the GPU + audio + pci bridge belonging to the GPU to a single CPU (CPU 3) and excluding that CPU from every other MSI interrupt.

All of those fixes worked for a reboot or two, but the only one that seems to have continued to work across driver updates and Windows updates is forcing PCIe to 3.0 mode