I recently got a Dell Inspiron 7490 which I love and I paired it with a basic Microsoft Bluetooth Mouse.
Unfortunately, an issue that seems to come and go is the mouse freezing when it isn’t used for over 5 seconds. This is long enough that it appears to be an intermittent issues with the mouse but is actually completely repeatable (just hold the mouse still and count to ten!).
After working through the various options, I narrowed this down to Power Saving on the actual Intel Bluetooth device. To fix this:
Go to Device Manager (simple press the Windows key on your keyboard and type Device Manager, then press enter)
Expand the Bluetooth section and locate the Intel(R) Wireless Bluetooth(R) device
Right click on it and select Properties
In the dialog box that pops up, click the Power Management tab
Uncheck the box that says Allow this computer to turn off this device to save power
Click Ok and you can now close device manager,
Problem should be solved!
Sadly the Power Management tab no longer exists for that device.