What render settings are you using? Kdenlive doesn’t use Movit for rendering but rather Melt. You can try AMD VAAPI under Hardware Accelerated in the Render menu. Some other tweaks you can do include enabling Parallel Processing (for your CPU, it can go up to 8), changing Custom Quality, and changing Encoder Speed (though the last two options do affect quality so experiment with what works for you)

Related Kdenlive Documentation

Shingled Magnetic Recording

Basically the write head writes over part of the magnetic track below the current track, reducing the physical size of each data and increasing how much data can be stored on one side of a disk.They’re bad for random writes because the drive would need to rewrite data in the track below it as well.

I’m not good with command line stuff but is sudo necessary if you’re already running as root?

i use lm-Sensors because it also shows temperature data, which is useful for what I do.