Upgrading the AMD drivers to an updated version is a Good Idea - see this post on The Register for an example - as the ones released by Lenovo are at least a year old. However, doing the regular upgrade wipes out the ability to use FreeSync with the built-in 144Hz screen, because it does a full settings reset and wipes the OEM customisations.
After some trial and error, the way to fix this is as follows:
- If you've already upgraded the drivers and lost FreeSync, use the AMD Cleanup Utility to delete any sign of existing AMD drivers.
- Reinstall the original drivers from the Lenovo support page for your laptop.
- Get the latest AMD Adrenalin software.
- Install it - but UNTICK the box that specifies "do factory reset". That's what breaks the existing configuration for FreeSync.
Successful results: