Victor123Fcpx wrote: ...Now I use an imac pro - i9 - 64gb ram - and it takes the same 1 hour.
on macbook pro used 80% of mac
imac pro uses 5%.
how to make imac pro decrease the time to save using more of its capacity?...
No iMac Pro has an i7 or i9, they only have Xeon CPUs. Export consists of two conceptual phases, render and export (or encode). Render is processing all edit steps and effects to intermediate ProRes cache files, either physical files if discrete timeline rendering or a rolling window of few frames if using integrated export of a non-rendered timeline.
The first step is evaluate whether the render phase is slow and different between MacBook Pro and iMac Pro, or whether the encode phase is different.
To do this disable background rendering in FCPX preferences, then delete all render files by selecting the library in the left sidebar, then do File>Delete Generated Library Files>Delete Render Files>All. After that pre-render the timeline with CMD+A to select all timeline clips, then CTRL+R to render to cache. Do this on both machines and time how long this takes on each. That tells you the performance difference for the render phase.
After that export the file to H264 on both machines, and time that phase. Use this preset: File>Share>Master File>Settings, Format: Computer, Video Codec: H.264 Faster Encode, Resolution: 1920x1080.
Make sure the timeline, effects and media are exactly the same on both machines. Report the timed test results for each phase on each machine, also re-check the CPU/GPU performance graph for each phase on each machine.
In general you can't make a machine use more CPU or GPU -- it's using all it can for the current situation. If the iMac Pro shows 5% CPU during export, that indicates it's bottlenecked on something else, such as waiting on the T2 chip to encode to H264. It could also indicate the iMac Pro timeline is pre-rendered and it's a pure encode case, whereas the MacBook Pro might be using a lot of CPU to render a non-cached timeline. So first step is re-run tests as stated above, making sure the render state and export presets are identical.
Obviously they should also be on the same version of MacOS and FCPX and use similar I/O, not a slow disk on one and a fast disk on the other.