Greetings Everyone!
I came to this topic suffering similar problem as you all. In my case though, the problem itself was slightly different. RX560 was visible in radeon settings app, however, whenever I was launching a game only integrated R8 Vega was available and no matter what I was trying to do, there was no chance to force computer to switch integrated GPU to RX560. You can easily imagine, that in more demanding games, quality of game-play was ultimately bad, making gaming laptop completely useless, not just in gaming but sometimes even in web browsing or video streaming (Yuhhh!!!).
I contacted Asus support (they should shut it down immediately, people working there have no slightest idea about managing computers and when it is coming to resolving technical issues or hardware/driver malfunction they are as useful as babies in the mist) but of course I received nothing useful from them. So I started looking on my own, getting ready to return the laptop and pick something with nvidia (ehhh, I was really pissed, actually I still am a bit...). Eventually I have come across with this topic and that was Eureka... just not immediately. So I will describe the path I needed to walk with all the issues I had during the process, to make it as useful and clear to everyone, who is suffering because of AMD&Asus negligence/stupidity, as possible. I hope it will finaly make your laptops work properly. It worked for me.
Before starting make sure that you have bios version 309. You can check what is your current version by pressing F2 on bios startup, before windows loading screen.
Step 1. DDU Safe Mode uninstall (essential step, no need to explain, nothing wrong or weird happened here)
Step 2. Installation of latest chipset driver from Asus support page (ver. 2520141501). Make sure that you will run install.bat as administrator, otherwise driver will not be installed and entire process will be useless. So don't double left click it, but right click and run as admin. During this step my screen got dark as usually, however it didn't auto restart itself after driver was installed. Pressing FN+F6 to turn off the screen, then press it again fixed the issue and let me to continue the process. I was expecting that the system will ask me to restart, however it did not, so I moved on.
Step 3. Installation of Adrenalin 19.7.1 from AMD website. As it was recommended by galentot before, I used express installation. Everything went smooth but system did not ask for restart again. I knew it is necessary though so I restarted my laptop.
Step 4. First launch after update. Computer hanged on windows login screen. Attention! Leave your computer in peace for a while, do not force restart it, it is not really hanging but applying drivers (at least I believe it is). In my case it took around 5 minutes, maybe a bit more before laptop was responsive again and I was able to login to windows and check if everything is ok. So I launched Grim Dawn... and it was fail. Still only integrated R8 Vega available. I cursed morons, who developed this nightmarish loop and sold it as gaming laptop and I was already opening the box, to shove the laptop inside and take it back to the store... However voice of final reason whispered to my ear, to check if everything is ok on Device Manager page. And it was not. Yellow "!" over RX560. Driver was not successfully installed. So I right clicked it, chose "update driver" then I chose directory with drivers downloaded from AMD. After update, RX disappeared from the list. So restart of the laptop and... And it finally works! I don't know what went wrong that driver for RX560 was not properly installed. Perhaps I caused the issue, because I did not restart the computer after Step 2. I'm too lazy to redo the process and check if that's the case. Anyways my problem is gone and everything is working as it should.
It was a weird and annoying path, but eventually my laptop is working normally. No more inactive RX560, no issues with flickering screen etc.
I sincerely hope, that my detailed and colorful explanation will help those of you, who still suffer this issue to finally get rid of it and enjoy smooth working of your computer. Because in the end, this is very good laptop (of course once it is without issues).
Best Regards for all AMD supporters! (even though AMD not necessarily deserves our support, creating loops and glitches like this one)
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