Power saving features on VIM2 v1.2?

Hello.

I have a VIM2 v1.2 kit with a Khadas’s DIY case, a Khadas’s heatsink and a Khadas’s cooler fan.

The board works fine for my scenarios, but it sometimes turns on its fan when it is in an idle state, which disturbs me at the night.

I’m using it as a dual-band Wi-Fi router, PiHole DNS filter, OpenVPN client, and a qbittorrent-nox client based on the Ubuntu Focal minimal image.
The System Load Average hasn’t breached a 2.0 level during idle usage (with all mentioned services were running).

The cooler fan is repeatedly turning on at 50’celsium degrees on the CPU.

I’m using a schedutil cpufreq governor and set it to 100MHz min freq using following commands:

for cpu in /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor; do echo schedutil > $cpu;done
for cpu in /sys/devices/system/cpu/cpu*/cpufreq/scaling_min_freq; do echo 100000 > $cpu ; done

When the cooler fan was on at 3rd speed (max) - the CPU temperature in idle became 38-celsius degrees after an hour of blowing the VIM2, but when I turned the fan control back to auto - CPU temperature quickly reached 50c degrees and the fan started to spin and stop again.

Also. I’m powering my setup (VIM2, USB HDD, and an Android tablet act as an USB modem) from the active USB2.0 HUB which provides the power to the host device over an uplink USB port, and I wanted to power my VIM2 using a USB-A socket near the USB-C port through the hub’s power capabilities, but when I tried this my VIM2 became unstable. I had to connect a USB-C power cable to it (from the same USB hub) to get my VIM2 stable.

Is there any way to lower power consumption and heat dissipation on the VIM2 V1.2 board like CPU undervolting or other devices undervolting and/or underclocking?
I would be happy if my VIM2 will stop overheating and will be able to be powered up using a USB-A port near the USB-C connector.

Could you please help me with this issue?
Thank you.