Something I've noticed about GPU utilization

Is it sort've just an issue of the present engine that very little, if any, GPU work is being done? I recently upgraded my rig and was seeing the as-usual-none-too-impressive FPS in Istaria.

Upon digging a bit deeper via GPU-Z I am seeing that my card is staying in "low power" mode due to "little to no GPU utilization." Even if I specifically set Istaria to max-performance, it just isn't seeming to use the card at all. Is the engine/DirectX simply so old that newer cards/OS versions will essentially overlook it entirely for GPU rendering?

I'm asking so I can assess how much fiddling with it I should do, and whether it's an inherent issue in the current engine in its current state with newer cards/OS, or what. :D

Thanks!

I also see that CPU use never really goes above 10%, but I am guessing this may be a core/multi-core related thing considering Istaria's age.

My Isatria usually uses around 17%. That pretty much looks like one core on 100%. And yeah when i set Istaria to use only one core it shows running at 100% for that core (without any performance change in game). I think its reasonable to expect that Istaria can not use more then one cpu core. So thats probably whats holding your gpu back. My gpu doesnt even bother to clock up when i launch the game and just stays at idle frequencies (yet i only get 20+- FPS because cpu is cluttered - old Phenom).

Istaria is limited to a single main thread due to the old game architecture, which is also why the GPU utilization is low. If you put in something like a GeForce 7600 GT from 10 years ago, those GPUs can be nearly maxed out by Istaria (and new GPUs are up to tens of times faster).

To get the best possible performance out of Istaria, you need to:
-Have the highest frequency CPU cores possible (preferably modern Intel Core i5/i7)
-Disable shadows completely or reduce to blob shadows only as a compromise
-Have as few windows open in the game's UI as possible
-Run the game at 1080p (1920*1080) or a lesser resolution, as high end 2560*1440 and higher monitors greatly diminish the framerate.
-Use the "DX9 Shaders" option in the launcher (which invokes the third party ENBSeries DX8 to DX9 converter)