OK, it's a rant as well as a success story...
I've had my ROG Strix SCAR III G531GW for a while and have always suffered from a poor battery. Independent reviews gave it 4 to 4.5 hours with average brightness surfing the web. I would've been happy with 3 but was getting 1hr 15 at most just idling. The schoolboys who built the OS had installed BETA drivers. And in the early days of owning the laptop I simply could not locate anything that did not have a BETA written next to it. I even contacted a support rep, and he gave me a download link to yet more BETA drivers! This was about 9 months ago. So I gave up. One day I plugged in a USB Linux key and didn't see much difference in the battery, so naturally assumed it was a bad battery.
However, as I was preparing my laptop for a return today, I found myself accidentally uninstalling the ArmouryCrate software. Well, actually, I clicked on 'Modify' install and the damn thing began to uninstall. I then downloaded the latest, installed it again, rebooted and left the laptop on for a final test. Literally a few hours before the RMA collection, I had been going 4 hours straight on YouTube! Cancelled the collection and here I am.
ArmouryCrate is/was? an absolute mess. They have written an unreliable and disconnected piece of software that is difficult to understand and work with. This concept of separating the service from the UWP application which is sometimes downloadable from the Windows Store and sometimes not, is just nonsense! Am I right in thinking this software is developed by Chinese developers? That would explain the complete alien nature and concepts they employ?
Anyway, if you're having battery issues, be in the knowledge that it might just be the ArmouryCrate software. I cannot explain it and during the 1hr 15min performance I was always on my SILENT profile but still juice was draining away.