Having done a lot of monitoring of my Latitude E5440 because of fan issues I spotted large CPU spikes every 9 seconds (no apps open or network traffic):

I can see it's caused by a group of "DcomLaunch" services.  My old laptop with same OS, software, Anti-Virus (Avast) does not show these spikes.

Looking at similar problems reported on the net it was down to a third-party service/driver or malware but I have done a full scan and it still occurs in Safe Mode:

I have also gone through disabling as many services and drivers as possible but no luck.  Seems like it must be something to do with power management?

Good job I'm not a gamer as a 25% CPU spike every 9 seconds would be totally unacceptable.