So I reinstalled windows 10 (21H1) today (without internet connection), and went through installing drivers from dell website.
Installed the AMD drivers from Dell (15.x), and everything was fine.
I then tried to install the latest AMD drivers (WHQL) from amd.com and froze during install, and now PC freezes on boot (and during AM.com driver install).
Drivers from dell.com seemed to be fine and was running stable for ages.
I'm going to boot into safe mode tomorrow (ideally a system restore point) and remove new drivers, and install old drivers again and leave it be on the really old drivers!
Issue is covered here - https://www.dell.com/community/Latitude/E6440-AMD-8690M-Driver-Update/td-p/7494198
I've also updated the BIOS from A11 to A24 (while it was stable)
@Gurezaemon you may want to check BIOS version on yours as A24 fixes many CVEs - https://www.dell.com/support/home/en-us/drivers/driversdetails?driverid=r5mdj&oscode=wt64a&productcode=latitude-e6440-laptop
@Shapenz - thanks very much for the laptop! Once get the Dell AMD driver working again I'm sure we'll be good to go!
AMD radeon hd 8690m