Thats because you are not using a Mac with a Vega video card. Its been confirmed on another thread that its a Vega specific issue.
Sat, Sep 7
Aug 7 2019
I would like confirmation that blender does not intend to fix this from the update from Will Crespo. So blender only partly works with Mac?
Jul 20 2019
Jul 19 2019
This is all I get when I open the file.
Jul 17 2019
How do I do that? This still isn't working with a 2018 MacBook Pro 2018 i7 Vega 20. It initially worked with the first fix. On version blender-2.80.0-git20190315.35b78d9807c4-x86_64 5.34.24 PM is the latest one that I use to get the noise textures to work in with Volumes.
Jul 9 2019
Tried the latest build. Still nothing. When I connect the Noise Texture node to the ColorRamp node everything stops working and I get no volumes at all. When I disconnect them I get the basic volumes back. No errors in the terminal.
Jul 6 2019
May 18 2019
This seems to be an issue again with the latest build. Having to use an older build now. Also where did User Preferences go?
Mar 10 2019
Can confirm its not working on a Mac. 2018 MacBook Pro with Vega 20 i7