AsRock z390 - stuttering

Hi there. I'm trying to troubleshoot a very strange problem.

My build:
9700k
RTX 2070
16gb RAM DDR4 3000 mhz
Seasonic focus plus gold 750W
AsRock z390 Extreme4

Every component is brand new.

I'm getting random stuttering in games like CS GO and PUBG. It manifests itself in frametime spikes, like from 3 ms to 120 in a very short time. It's not connected with situation on screen.

During troubleshooting process, I managed to rule out other PC components, like ram, gpu etc. Done memtests, used furmark (no spikes), occt stability tests, flashed bios, did few windows clean installs and clean boots, tried multiple version of drivers, nvidia panel settings, game settings. No results.

I tested the PC in my parents' home - no difference, issue persists.

It might be connected with online gaming - and intel ethernet controller, as stutters are connected i.e. with situation when someone joins the server, just like on this video.

https://www.youtube.com/watch?v=vswm8S7mya0

I RMA'd whole cpu, they didnt spot the issue, so I got the PC back. They suggested that this could be a motherboard issue and taught me to RMA it.

Now I'd like to ask - is it a good idea to RMA the mobo? Can it be a cause? Thanks for help!
Mike

Yes, it is...

Over the year I've built many computers and I have never experienced a problem with the physical on-board Ethernet port. Of course I could also just be a lucky sole. Now problems with a driver have certainly happened and often I found myself visiting the hardware manufacturer's web site in a quest to find the most up-to-date driver file.

From what you wrote it would appear that you are suspicious the Ethernet port might be the culprit, but I did not get the impression you were able to perform any type of testing that would help to verify this hunch. A few days ago I noticed forum member jskibo made a post about slow lan speed with a Z390 Taichi board. Apparently reverting back to an older Ethernet driver helped to partially resolve the problem.

http://forum.asrock.com/forum_posts.asp?TID=11559&title=z390-taichi-slow-lan

Focusing on the Ethernet port, and before sending back the board, it might be worth running some tests to see if there are problems with high packet loss or jitter. I'm embarrassed to ask, but I assume you did try a different Ethernet cable. :)

Anyway, if you don't mind using command line utilities, you might try using the program iperf to run some tests against one of the public iperf servers or against another computer on your lan acting in the role of an iperf server.

https://iperf.fr/iperf-download.php

I have used the 64-bit version with Windows 7 and experienced no problems with the utility. I assume it would work okay with Windows 10, if that is what you are using. There is nothing to install, just unzip the iperf files into a folder.

It is rather simple to start an iperf server on another computer connected to your private lan. Open a command prompt window and, from where the iperf files are stored, simply enter the command... iperf3 -s

By default the port used is 5201 so upon first execution the Windows firewall might prompt to allow access to the port.

Then from the Z390 Extreme4 computer you can execute tests using the Ethernet port. A few tests that you might try (where 192.168.xx.xx is the ip address of the computer running iperf3 -s)...

Test upload speed
iperf3 -c 192.168.xx.xx

Test download speed
iperf3 -c 192.168.xx.xx -R

Or using one of the iperf public servers
iperf3 -c bouygues.iperf.fr
iperf3 -c bouygues.iperf.fr -R

Test packet loss and jitter (assuming a 100BaseTX lan)
iperf3 -c 192.168.xx.xx -u -b 100M
iperf3 -c 192.168.xx.xx -u -b 100M -R

By default a test will run for ten seconds with a measurement reported every second. To extend the test time include the -t xx option where xx is the number of seconds.

When running these tests iperf will attempt to saturate the lan with packet traffic so for best results try to avoid using other applications that will access the lan at the same time, or when other family members are watching Netflix. :)

If you are not a fan of command line utilities then you could try using one of the online internet connection testing tools such as DslReports...

https://www.dslreports.com/speedtest

https://www.dslreports.com/tools/pingtest

Another one to try, that allows the test file size to be manually set, up to 200mb, would be...

https://testmy.net

Of course using these online tools leaves you at the mercy of your isp and the varying conditions of the internet. If you plan to try different Ethernet drivers then running iperf against an iperf server sitting on your private lan would produce the most consistent test results.

I wish you luck.

I'm Japanese, so my English is poor, sorry.

I use Z390 Phantom 6 (bios 4.10) and have same problem.
I try to setting bios as follows.
/Intel Turbo Boost is off.
/Intel Speed Step is off

Then, stuttering is not happened while one week.

Now, the bios 4.20 is released today.
I will update bios from 4.10 to 4.20.
I hope bios 4.20 work fine under Intel Turbo Boost and Intel Speed Step functions.