If you want a "one-click" fix, use Dell's pre-installed maintenance tool: SupportAssist app on your Dell PC. Get Drivers & Downloads
The (System Management Bus) is a motherboard chipset component responsible for monitoring hardware voltage and temperature. On Dell systems, a yellow exclamation mark in the Device Manager usually appears after a Windows 10 reinstallation because native drivers for the specific chipset are missing. How to Install the Driver on Dell (Windows 10 64-bit) sm bus controller driver windows 10 64 bit dell