All over Google and I assume the entire internet I keep seeing the question about the SM Bus Controller in device manager and there’s almost as many answers as questions. I had the exact same problem and in my case it was on 2 different computers that weren’t on a network. I also had a ? beside Other PCI Bridge Device and a third file I can’t remember. All 3 files were under the heading Other Devices which also had a yellow question mark beside it. I finally realized that I had been moving my SIIG 5.1 sound card back and forth between the 2 machines depending on which one I was using at the time. I removed the card and the associated software, enabled the sound system on the mobo and guess what? No more yellow question marks. I must have spent 40 hours trying get rid of those things and now I’m one happy camper.
