The “Redstone 3” train has left the station, and it’s picking up speed: For the third time in less than two weeks, Microsoft has released an Insider Preview build for “Redstone 3,” the next major version of Windows 10.

As you may recall, Microsoft issued 16170 on April 7. It didn’t offer any noticeable changes or new features, but instead focused on OneCore refinements and some code refactoring and other engineering work.

Last Friday, Microsoft delivered build 16176. This one offered just a single minor functional change—the Windows Subsystem for Linux (Beta) can now access Windows COM ports—but was otherwise also about under-the-hood changes.

Today, however, Microsoft released Windows 10 Insider Preview Build 16179. So what does this third pre-release “Redstone 3” build bring to the table?

Two new features, as it turns out:

Revert VM. Hyper-V now offers automatic checkpoints so that you can always undo any mistakes in a virtual machine. So you can now revert to the last time you started that virtual machine. (Hyper-V has long supported checkpoint functionality that lets you save a VM slice-in-time so you can always go back to that point.)

Power Throttling. As we discussed yesterday, Power Throttling was originally intended to ship in the Creators Update, but it looks like it will finally make it to Windows 10 as part of RS3. Microsoft notes, however, that the name is not necessarily final: It may change this name before the final release.

This build also includes a number of changes, improvements, and fixes, plus a few known issues. Check out the Windows Experience Blog for more information.