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High DPC Latency

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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I'm not certain I can trust what I'm seeing. It looks to me as if the dxgkrnl.sys calls to an ISR are regularly exceeding the recommended upper limit of 25 microseconds. The average is 1.5 milliseconds which is not good for overall performance but I see quite a few exceeding 22 milliseconds which would cause audio glitches. One was even 90 milliseconds which is an incredibly long time for an ISR. The above is all happening on core 0 which is where most (if not all) of the audio processing is done.

ISRs can be interrupted by higher priority ISRs but I don't see evidence of that happening. It makes me think the new GPU has a hardware problem.

There is also a span where atapi.sys takes a long time but it's happening on core 1 so shouldn't be interfering with audio playback.

Unfortunately, I'm not sure if capturing the trace is causing some of what I'm seeing. It does have an impact on performance and, if there are not a lot of resources to spare, can actually cause problems during the trace the system wouldn't experience normally. Such as running out of physical memory and hitting the pagefile more frequently.

Did you replace the GPU because you were having problems with the old one?
 

Josue Torres

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Hardware Problem? I was really careful when taking the GPU out of the box and everything, but I didn't do a visual check to see if everything was fine. I will probably check the GPU carefully and closely. But, if it was a hardware problem, then why do the audio issues (and the latency from dxgkrnl.sys and all the others ) vanish when the Nvidia Drivers are uninstalled? No! My nvidia geforce 210 was working perfectly fine! Just wanted a little upgrade haha!

Should I do another ETL test with Nvidia drivers uninstalled (because that makes the problem dissapear) and send it to you?
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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I've seen GPUs have problems while doing certain things and not others. My guess would be Chrome is using the GPU for hardware acceleration which is using features of the GPU which don't get used for normal desktop functions. It might be helpful to see how the system behaves without the Nvidia drivers so please do make a 15 second trace of playing a video in Chrome with the drivers uninstalled - whether or not it has any audio glitches.
 

Josue Torres

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Here is the link to the compressed general.etl file!

Test 2, Without Nvidia drivers, while watching youtube video, no audio issues and no latency at all. I took a screenshot of LatencyMon so you could see the difference.
general2.rar - Google Drive
Capture.PNG
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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I got it, thank you. I'll have a closer look but a quick glance shows a much better story as far as ISRs and DPCs. Does device manager show a generic display adapter rather than an Nvidia adapter under the "Display adapters" node?
 

Josue Torres

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You're Welcome!
Device manager shows "Microsoft Basic Display Adapter" under the "Display adapters" node.
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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Okay. So that basically means no hardware acceleration at all from the GPU. Everything is done in software and the videocard is just displaying what gets rendered by the CPU. Which explains why the poor CPU is pegged at 100 percent through the whole trace. That would lend credence to the idea of a faulty GPU. Would it be too much trouble to install the old GPU, install a Nvidia driver, and get a trace with a video playing in that system configuration?
 

Josue Torres

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No problem! Just that it will be tomorrow since i'm a little busy right now. I'll also do a visual check on the GPU to see if there is something unusual and will let you know!
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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It looks pretty good and I don't see anything that would be causing audio glitches so it matches what you experienced. Did you use driver version 342.01 for the G210? The latest Nvidia driver is 416.81 but 342.01 is the last version which is compatible with the G210 according to the Nvidia driver download site. The display adapter configuration information seems to be missing for some reason which was true for the trace using the Microsoft driver. The drop in CPU usage would suggest the GPU is doing the graphics work but can you check in Device Manager to make sure it's showing a Nvidia device?

It looks like there were a few more processes running in the GT710 trace but I don't think they would be more than the system could handle. Spotify wasn't running in the G210 trace so less network traffic was going on but I still don't think it would make the difference. I'm going to try and compare the two to see if I can figure out if it's a driver or software issue but I'm still leaning towards the new GPU being defective. I thought it might be a power issue but power requirements should be the same according to the specs.

Please let me know which Nvidia driver you used for each GPU and if you've tried installing only the graphics drivers for the GT710 - meaning selecting Nvidia Graphics Driver (rather than Nvidia Graphics Driver and Geforce Experience), Custom (Advanced), install without installing Geforce Experience, uncheck all of the custom options that can be unchecked, and then selecting Perform a clean installation.
 

Josue Torres

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I used the latest driver version for the G210 which is 342.01, I use Geforce Experience for installing my drivers and always do a "perform a clean installation" so I have no problems. It did say Nvidia Geforce 210 in the device manager. Too bad I don't have another PC to test the graphics card to really know if its defective. From what I read G210 and GT710 have the same power requirements. I used the latest drivers for both GPU's. Ummmm. I'm not sure what you mean with that last paragraph. I use Geforce Experience to install the drivers, so I guess you are trying to tell me if I have downloaded the drivers and installed the .exe? I'm going to try that. Correct me if I'm wrong.
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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Correct. I basically want you to do a minimal install using the installer downloaded from GeForce.com Official Site: RTX Graphics Cards, VR, Gaming, Laptops so that nothing but the graphics driver gets installed. I know Geforce Experience has services for casting and recording (perhaps others) but I'm not sure if they are enabled by default. I'm just trying to see if something about the software or optional drivers is pushing the computer over the edge as far as what it can handle. I don't get that impression from the trace but I'd like to make sure, if possible.
 

Josue Torres

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I just downloaded the driver and installed it manually, did all you told me, only installed graphic drivers and unchecked all others, still the same problem.
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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Has the resolution and/or refresh rate increased with the new GPU vs the old?
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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Apr 3, 2017
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Does it have the same problem playing videos in Edge?
 

Josue Torres

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I checked with a couple of videos and... surprisingly... there are absolutely no audio issues or video stuttering even though latencymon shows over the sky latency for dxgkrnl.sys.
 

cwsink

Sysnative Staff, BSOD Kernel Dump Expert
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Apr 3, 2017
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Would you make a trace of that for comparison? 30 seconds should be enough.
 
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