Latitude E5540, system interrupts high CPU usage 15-30%

Hello,

Sorry for my English. I would like to ask you. I use Windows 10 64-bit. The purchased warranty expired on February 18, 2018. I noticed system interrupts still loads CPU about 15-30%. I tried for example update all drivers, clean Windows installation etc. but nothing helped me. It is very annoying because fun is still ON. I found same problem on internet but nothing helped me. For example this link. Please can you help me?

Thank you.