Where to find the Synchronization controls in Win-8.1

Just in case, like me, you want to turn them OFF. See these screenshots below:-

The above shows them all turned on. (Black slider to the right in each switch.)

Here they are, all off. (The top switch on the page shuts off everything but the second one, just below it. You have to switch that one separately.)

This, as my handy All CPU Meter shows, will save a hell of a lot of loading on your nice little CPU, and let it run much cooler - which could be something to consider, especially if you're on a laptop which normally tends to run hotter than hell anyway. And before cute little Sally down at Microsoft sends me a sharply worded email, let me hasten to explain that I just love these modern conveniences, but only if they're convenient for me - not for somebody else.
I just recently rescued this old PC from a fate worse than death, and I don't want its CPU to get fried now from being overloaded with unnecessary work.
Maybe for you, this isn't a concern, and if so, please disregard the above, But if you're like me, this could save you some trouble and expense later.

Here's the gadget monitoring my CPU, and as you can see, it's cores are not spiking up near the top of the graph now - they're quite peaceful & happy - and not nearly as hot. Trust me - your CPU will last longer if you're nice to it.