I am running Windows 10 Technical Preview on a Surface 3. The Host Process for Synchronization Settings is consistently using 25-30% of the CPU. I've seen threads on similar problems in Windows 8.1. Those threads suggest its a security issue in the registry and that turning off the Synchronization will also fix it. I've turned off Synchronization of all settings and checked the permissions referenced. In my case the permissions are correct and I've rebooted twice since turning of Synchronization and the Host process for Synchronization Settings is still using 25-30% of the CPU. If I kill the process using Task Manager the CPU returns to normal for a while, but the high utilization comes back after a while. Its not causing a big problem, but does cause the fan to run constantly.
Anyone else seeing this on Windows 10?