there's no reason an i3-4000 cannot support a KNC, as far as I know.
You say "device detected but not picked up by mpss"
Which OS are you using? Can you run 'micdebug.sh' (Linux) or the Windows equivalent and post the output here. That might give a clue as to what is failing. My main suspicion would be the power supply or cooling fan of the board - a 7120P KNC uses quite a lot of power and requires STRONG active cooling (as it does not have a fan of its own)
//Which OS are you using?
I tried CentOS 7.4 - 6.4.
//Can you run 'micdebug.sh' (Linux) or the Windows equivalent and post the output here
Ok, as soon as I assembly my test-stand back.
...For KNC P means heat sink supplied, you supply the fan. I use dual 5100P's and built my own fan ductwork and selected appropriate fans.
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