Take it down a notch “bro”. I apologize if my post sounded like if I was a bit angry, but it was nothing against you. The whole Cubase program is literally based on VST code, it’s like a giant modular plugin where every component like volume faders, panners, etc, is a VST module. So is the graphical aspect.
For example I have a project which takes around 2% CPU at idle. When I open SuperVision and set it to Spectrogram, Cubase.exe CPU usage goes up to 10%, and this is even with the transport on Stop position, SuperVision being the only plugin in the session. As soon as I close the SuperVision window, CPU goes down to 2% again. And in both cases, GPU load does not change, because everything is drawn by the CPU anyway.
Same test with the Performance Meter : from the 2% CPU at idle; when the Performance Meter is open, the CPU for Cubase goes to 4%, so what the Performance Meter shows is already biased by the fact that CPU usage increases when it is open…
So to summarize all of this, the more animated assets are displayed by Cubase, the more CPU it will take, because it does not use the GPU. The GPU only refreshes the final frame, and its usage may increase a little when there is more happening on the screen because there is more pixels to change, otherwise when the image is static there is nothing to change and it reuses the data. In any case, Cubase, or VST (this is the same to me, yes), is in no way GPU accelerated and this is the issue.
As of limiting the FPS in the driver will reduce the peaks on the CPU, yes it will, because the graphics counterpart tells the CPU to only pre-render this amount of frames per second.
15~20% GPU usage may only be 15~20% of a very low clock (150 MHz for example), so if your GPU was running at max clock it will be only 1% or less. This alone proves that Cubase isn’t GPU accelerated on Windows. (however it is on Mac) (this linked topic also tells that Cubase on Windows is locked to 60 FPS, which is also what I have noticed. Cubase is not even using the Desktop’s refresh rate, nor is VRR aware (VRR= variable refresh rate). Instead it is locked to 60, that’s why is looks all stuttery when the screen has a different refresh rate than that.)
(@Googly_Smythe @Norbury_Brook The OP is talking about CPU peaks, as interpreted by Cubase’s Performance Meter, not about GPU usage.)
I have downloaded your screenshots, and indeed we can clearly see that starting from Cubase 12, the CPU usage increases noticeably. Not only that, but it runs on Core 0 and 1, as opposed to Core 0 and 5 prior to version 12. This is problematic because Core 0 and 1 is where most of the system runs, and in this case there is less headroom for Cubase on that core. This explains why the CPU graphs are a bit higher.
Moreover, your screenshots from Cubase 14 show that ASIO-Guard is disabled, which explains why the CPU load is tremendously higher on these two cores compared to Cubase 12. I bet that if you enable it, it will be similar to Cubase 12.