CPU Spike Stutter FIX AMD 5900x / RTX 4090 / Win 10

Decided to post this here because there doesn't seem to be knowledge about the fix on this problem.

First and for most CPU LAG SPIKE doesn't have anything to do with the ping. So don't think they are the same.
Those who are trying this I expect you know what you are doing and I'm not taking any responsible if somebody fails or bricks their computer or windows.

So lets get started:
https://imgur.com/a/c5cJwF7

Starting point image we can see clearly we have CPU spike along with Frame time spike. This looks like game lags or stutters if you try to move you see character freezes periodically. This stutter happened every 15s so it was consistent. This spike would get really bad on fights and game seems like really laggy or playing on really high ping.

After through debugging the fix comes with following:

Preliminary steps:
Nvidia Control panel set 3D settings -> Power Managment mode - > Prefer maximum performance

Disable High Precision event timer in bios and in Device Manager in Windows

After that we start looking the culprits:

1. Download Latencymon 7.20 [Removed by Support]
We use this software first to debug all driver issues.
Launch Latencymon don't do anything with it yet.
Then launch Poe and go Act 6 and twilight strand and leave the character at the gate.
This was most consistent spot to debug the problem.
Now after you have character in place open performance graph out so you see CPU spikes now Alt Tab to Latencymon and press start now alt tab back to Poe and just wait without moving atleast 2min.
After 2min Alt Tab and press stop in Latencymon and close POE after this.

Now go to Drivers tab and if you see some driver with High ISR count those drivers most likely have something wrong. All these drivers are different from machine to machine but principle stays the same.
If you see high ISR count on Wdf01000.sys this is Windows core layer that count's other errors too.
After you have fixed all other driver problems usually meaning installing manufacturer's original driver instead of windows generic one.
You can always google (Latencymon xxxx.dll) to find info what could the culprit be.
If you still see high ISR and DCP count on Wdf01000.sys go to step 2.

2. Download Guru3D MSI utility V3 from [Removed by Support]
Download link is on first post.
After downloading you need to right click and run the program as Administrator.
Now if you see on supported modes Msi text and the checkbox ain't checked. Check the checkbox and press on top right Apply.
After this reboot the machine.

Now repeat the Act 6 Twilight strand test this fixed it for me and now I have 3ms Frame time and 288Fps with 0 Stutter.

Thanks for your post.

1. Got high ISR-counts on HDAudBus.sys, dxgkml.sys and wdf0100.sys - After many searches, I coulnt find out yet, how to solve it (updated drivers, updated bios), However, at least I have now more clues and a test that gives me numbers to monitore the problem. EDIT: After a restart, the ISR-Counts of HDAudBus.sys & dxgkml.sys diappeared. The only fix I tried before restart was the MSI fix, I believe, or some other fix suddenly worked for the counts. However, my spikes/stutters stayed, at least a step forward :D

2. Do you check all boxes for MSI Mode or just one certain?