Right.
Downloaded MEI from Asus site.
Uninstalled old one as per maf23's post (thanks).
Reboot, reinstall and.............. the version number shows up as exactly the same as what was there before!
Short of checking and trying to reinstall every driver, or reverting laptop to original state and hoping win update doesn't change to as is - not keen on that option just now, it looks like I may just have to put up with the faster ramp up in speed of the fans, etc.:(
Maybe straight out the box they were not spinning up enough and this is an intended change, or maybe I am just getting used to the new levels. I think if it had run at these levels initially I probably wouldn't have thought too much about it but .....