P150EM upgrade GPU to GTX 1060

If you are still looking post any card you find for guidance before buying.

 

I know this is an old topic and I was the only one facing this very specific issue AFAIK but I finally found a solution and decided to post it here, just in case someone with this issue finds himself here.

Short version: Windows 10 fixes the issue.

Long version:

As I said, the latest driver that was partially working (only AAA/DirectX games worked, Java games like Minecraft were running on Intel HD Graphics) was 425.31. Any driver above that resulted with all games running on Intel HD.
Windows 10 wasn't an option because it couldn't support the fairly old 425.31 drivers and therefore faced the same issue as 8.1, only using Intel HD in games...

However, Windows 10 Insider Preview Build 19564 introduced the new Graphics Settings which at first glance seems very similar to the "Use Nvidia High Performance GPU" option. But I gave it the benefits of the doubt and gave a try to Windows 10 latest update 2004 with Nividia 446.14 drivers.

And voila ! My GTX1060 is detected and used in every AAA/DirectX games, even Minecraft Java Edition is working smoothly now. I can rest happy now.