Question High DPC latency and Turbo Boost

Aug 22, 2019
Hello. I experience heavy audio dropouts and crackles when Turbo Boost is on.

What I've noticed:

-It doesn't happen in safe mode.
-When I deactivate GPUs while playing audio, crackles disappear for a while.
-It works fine during first minutes after system boot.

My specs:
Laptop: Lenovo Legion Y530
CPU: i5-8300H
GPU: Nvidia GTX 1050ti

I have tried disabling services, reinstalling drivers, tweaking bios. Nothing has helped.

Here is a conclusion from 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. At least one detected problem appears to be network related. In case you are using a WLAN adapter, try disabling it to get better results. 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 0:20:33 (h🇲🇲ss) on all processors.

Computer name: ASUKA-STRIKES
OS version: Windows 10 , 10.0, version 1903, build: 18362 (x64)
Hardware: 81FV, LENOVO, LNVNB161216
CPU: GenuineIntel Intel(R) Core(TM) i5-8300H CPU @ 2.30GHz
Logical processors: 8
Processor groups: 1
RAM: 16258 MB total

Reported CPU speed: 2304 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.

WARNING: the CPU speed that was measured is only a fraction of the CPU speed reported. Your CPUs may be throttled back due to variable speed settings and thermal issues. It is suggested that you run a utility which reports your actual CPU frequency and temperature.

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): 4079,20
Average measured interrupt to process latency (µs): 4,824189

Highest measured interrupt to DPC latency (µs): 4074,30
Average measured interrupt to DPC latency (µs): 1,602581

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): 367,009549
Driver with highest ISR routine execution time: ACPI.sys - ACPI драйвер для NT, Microsoft Corporation

Highest reported total ISR routine time (%): 0,004299
Driver with highest ISR total time: ACPI.sys - ACPI драйвер для NT, Microsoft Corporation

Total time spent in ISRs (%) 0,005952

ISR count (execution time <250 µs): 85688
ISR count (execution time 250-500 µs): 0
ISR count (execution time 500-999 µs): 10
ISR count (execution time 1000-1999 µs): 0
ISR count (execution time 2000-3999 µs): 0
ISR count (execution time >=4000 µs): 0

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): 4249,995660
Driver with highest DPC routine execution time: ACPI.sys - ACPI драйвер для NT, Microsoft Corporation

Highest reported total DPC routine time (%): 0,044897
Driver with highest DPC total execution time: dxgkrnl.sys - DirectX Graphics Kernel, Microsoft Corporation

Total time spent in DPCs (%) 0,143738

DPC count (execution time <250 µs): 4552448
DPC count (execution time 250-500 µs): 0
DPC count (execution time 500-999 µs): 1100
DPC count (execution time 1000-1999 µs): 100
DPC count (execution time 2000-3999 µs): 123
DPC count (execution time >=4000 µs): 0

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: system

Total number of hard pagefaults 3813
Hard pagefault count of hardest hit process: 1386
Number of processes hit: 37

CPU 0 Interrupt cycle time (s): 67,884440
CPU 0 ISR highest execution time (µs): 367,009549
CPU 0 ISR total execution time (s): 0,586520
CPU 0 ISR count: 85402
CPU 0 DPC highest execution time (µs): 4249,995660
CPU 0 DPC total execution time (s): 13,599702
CPU 0 DPC count: 4467755
CPU 1 Interrupt cycle time (s): 36,939009
CPU 1 ISR highest execution time (µs): 27,123264
CPU 1 ISR total execution time (s): 0,000540
CPU 1 ISR count: 292
CPU 1 DPC highest execution time (µs): 565,968750
CPU 1 DPC total execution time (s): 0,114419
CPU 1 DPC count: 19287
CPU 2 Interrupt cycle time (s): 30,157725
CPU 2 ISR highest execution time (µs): 2,503472
CPU 2 ISR total execution time (s): 0,000008
CPU 2 ISR count: 4
CPU 2 DPC highest execution time (µs): 2010,574653
CPU 2 DPC total execution time (s): 0,249665
CPU 2 DPC count: 24224
CPU 3 Interrupt cycle time (s): 31,390815
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): 534,755208
CPU 3 DPC total execution time (s): 0,031111
CPU 3 DPC count: 7079
CPU 4 Interrupt cycle time (s): 29,800053
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): 559,128472
CPU 4 DPC total execution time (s): 0,049126
CPU 4 DPC count: 10566
CPU 5 Interrupt cycle time (s): 25,825060
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): 426,445313
CPU 5 DPC total execution time (s): 0,027708
CPU 5 DPC count: 5819
CPU 6 Interrupt cycle time (s): 27,703501
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): 715,406250
CPU 6 DPC total execution time (s): 0,062159
CPU 6 DPC count: 9512
CPU 7 Interrupt cycle time (s): 27,754249
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): 349,143229
CPU 7 DPC total execution time (s): 0,044645
CPU 7 DPC count: 9534

How can I fix crackles without disabling turbo boost?
Last edited:
Aug 22, 2019
Have you tried disabling all power saving settings in bios? And try using high performance in windows power settings.
I disabled C-states and all the crackles disappeared. But why everything worked fine in safe mode even with C-states enabled? Maybe there is a way to fix the issue without such a dramatic increase of power consumption?


Mar 31, 2019
Honestly I can only guess without being in front of the computer. But in safe mode it dosnt load as many drivers, so it may be a bad driver, I would start with audio drivers first. And the latency mon reported it may be a bad network driver. See if it needs updating, or even rolled back if it was just updated. With the power set to normal, or no power savings, it may be keeping your cpu from stumbling from the bad driver.
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