Media Browser painfully slow

Hi all!

I'm using the media browser panel to review my shots and pull them onto the timeline and I'm finding that the media browser is painfully slow to load the thumbnails, and every time I change workspace all the thumbnails that it took so long to process are gone and it has to do them again.  Is this normal?  In the past I just imported everything from my shoot and worked from the project panel, but this time I was thinking it would be more efficient to only import the actual takes I'm going to use.

What mystifies me is that my PC is actually pretty powerful on paper.  Maybe I'm missing something obvious that's causing the load times to be dreadful?  Here are my specs

PP CC newest (apr 2018) version

CPU: i7 6700k

RAM: 64GB

OS/Adobe install drive:  Samsung evo 850 SATA III Drive

Media drive: Samsung evo 960 nvme m.2 drive

Windows 10 current version (not that I have a choice on version)

GPU: GTX 1080

Ram setting in preferences gives 52GB to adobe CC and 12GB to everything else.

I can't think of any reason this shouldn't be screaming fast with my specs, but on the other hand I haven't used media browser much...