New CNC mill build

Hi, i want to build cnc mill a i trying to solve big problem. I want to use Odrive controller (2x controller, one for X a Y and second for Z and spindle). I want to use some single board computer (like Rasberry Pi 4) or some new PC motherboard, i dont want to use old computer. What is best hardware combination due to performance and price (RPi4 + FPGA board + BoB or PC motherboard+BoB) ?

I celebrated when I saw RPi4 among the recommended PCs for LinuxCNC. I immediately bought one RPi4.
I tried RPi4 + Mesa 7i96 for:
zz912.webnode.cz/galerie/
Numco KC6
It did not work good. RPi4 was so slow. I made jog and machine made jog after a few seconds. It was a very dangerous.
Sometimes I run LinuxCNC and CPU was under 25% and everything was OK.
Sometimes I run LinuxCNC and CPU was greater than 25% and LinuxCNC was unusable.
Mayby I made same mistake, but I dont know what. I had to use old PC.

The fact that there is no guaranteed hardware + guaranteed setup for LCNC is one of its weaknesses.

I've heard many times that LCNC works on anything. This is probably true, but it only applies to IT experts.

Note that in general if you want responsive jogging
it should be done in real time, then it is not delayed by OS
scheduling

Sometime I run LCNC:

And CPU is fantastic everything works.

Sometime I run LCNC:

And CPU dont want fall down under 25% CPU and it is problem.

I did these 2 attempts in a time span of 3 minutes. I didn't turn on any apps.

There is an error, some random number generator determines when the LCNC is usable and when it is not.

I bought 10 pcs of Mesa 7i96 (a total of 20 pieces, but 10 pieces for me), so I have enough hardware for experiments, but I don't have IT knowledge to solve problems.

At the moment, the unusability of RPi4 does not bother me. It bothers me more:
forum.linuxcnc.org/38-general-linuxcnc-q...ong-preview?start=10

RPi4 + Mesa 7i96 would be a good selling item if it worked.

What task is using that much CPU?

And that's the strangest thing - nothing.

That's strange I have a test setup with a 4G RPI4 and its pretty snappy even with more then 50% CPU utilization, though this is using Axis