Got almost the same situation. Thanks for the Task Manager tip.
But I have to say that A GeForce RTX 2060 is really good when video editing with DaVinci Resolve, but Blender is nothing faster now comared with my old PNY Nvidia K4000 GPU. It's very disapointing
Make a mesh.-
Your example has 4 vertices and two faces making a rectangle of two triangles, going to need a bit more geometry than that to have rounded corners. The same method applies here to making a mesh.
Given blender has a built in tool to make meshes, let's make a plane with bmesh, bevel the corners, triangulate it, and scale to suit.
Bevel & ...
He a little explanation about GPU vs CPU rendering in Blender:
GPUs are generally faster than CPUs, if you spend the same amount of money for them, so if you spend 500 dollars on a GPU and on a CPU, the GPU will be several times faster in rendering.
CPUs are made to run code, not to crunch numbers. They CAN, but they are more inefficient doing it. GPUs on ...
Low fps depends on the complexity of your seen. No matter how high specs your computer has, if your seen is complex, your playback speed may be low. You may need to divide your movie into smaller scenes.
I think Slow playback speed is a known issue of blender. You need to disable all subdiv surface modifiers, avoid high resolution simulations, ...etc.