my pc spec is older than yours (i7-2600K + value ram DDR3 16GB ) ..no GPU summore. Just built in GPU. Still can use Lightroom CC / Photoshop CC / Illustrator CC without heavy lag. My photo edits appear on screen near instantaneous. Yeah, not tip top but i can use it without annoying wait every time doing photo edits. I'm constantly running Lightroom with Chrome (~20 tabs open) AND Firefox (40-50 tabs open) consequently ...
well, too lazy to close the browser tabs ..

1. Are you sure your installation / drivers / windows 10 not causing any issue?

2. Have you pinpoint what apps is/are causing the high cpu + RAM in the task manager? For me, 70-90% CPU usage is usually when exporting the photos.

3. Is the CPU freq always at maximum or minimum? If it is minimum (not maxed out) most of the time, it could be that CPU is too hot. Thus, CPU always in slow freq at all time.

*But I'm tempted to change to Ryzen5 3600 one day. No rush, bcoz i can still squeeze this i7-2600K. LOL!

This post has been edited by mmohdnor: Jul 23 2019, 01:53 AM