The way to address this problem is to first look at what it is we actually want. Do we want smooth flow in the simulation, irrespective of scene complexity rising and falling? Do we want stable fps mostly, and high fps a desirable second.

Each PC has a performance capacity or capability to perform at a certain rate of fps not particularly governed by the CPU but rather the GPU.

We select what fps we want by adjusting settings. If we want high fps we turn down the settings or reduce the display area.

We need to see the CPU and GPU below 100% by tuning settings and the hardware matching capabilities. But also be able to see the CPU reach 100% with more severe settings.

With the relaxed system, when a scene increases in complexity we have overhead in the system to continue at the consistent rate.

With a stressed system, no overhead, the flow rate of the simulator varies with the scenario loading. That actually is a valid way to set things up if we want that.

On 8/8/2019 at 5:11 AM, Gabe777 said:

Thanks for the detailed info Westman.

As a matter of interest, you say the i9 9900k with HT set to OFF, is your best option. What estimate would you place on FPS and Smoothness gains, compared to to the i7 7700k. (I am guessing FPS would only be around 20 to 25 percent better ?)

I currently run the i7 7700k at auto turbo..... all 8 threads at 4.5. But as I run at 30 fps fixed, wonder if there is a benefit to upgrading to the i9 ?

I really want 60 fps at least for low n slow vfr, but if I try that currently,  I can get 60 for a lot of the time, but tend to get a lot of blurry scenery coming down to land and autogen that has disappeared. 

Fixing FPS at 30, cures all that.

Maybe I am better waiting for a large increase in power, from the next or one after.... the 11 or 12000k ?!

I believe we are quite a ways away from mainstream 6-7 ghz with current tech, the trend in both software and cpu hw is toward threading, not raw ghz.

The benefit of upgrading your i7 7700k to i9 9900k would be that your 30 fps would be maintained in more nasty places more or the time. 

In my own situation (8700K) I await the Comet Lake gen to see what that brings us.  I don't really expect much in the way of IPC improvements -- maybe a little.  Rather, I expect the sims to continue their trend towards gradual farming out of main thread tasks to other cores.   It's been a slow slog but it is happening, gradually.  And now with Microsoft Flight Simulator we may (?) be seeing some tasks moved out to the cloud...potentially further freeing up the local cpu for other tasks...time will tell on that front, however.