I am a forum noob here, so I'm not exactly sure how to reply your posts.
I amended my replies below.
CPU: 3800X Zen 2 / 9900K
Clock speed stock: 3.9 GHZ, 4.475 GHZ Boost / 3.6 GHz, 4.7 GHz Turbo
Memory: 2x8GB CL14 3200MHz / 2x8GB CL19 3600MHz
Office 365, Excel, Version 1902: 64 bit (same)
Time: 47.39 secs / 50.79 secs
I also tested a 2700X with the same Mobo, RAM and Excel Specs as the 3800X
What really baffles me, and I think there must've been an update to Excel is that:
1. 9900K tested on 4 May, 50.71 (I cant recall the Excel version)
2. 9900K tested on 30 July, 50.79
3. 2700X tested on 29 Apr, 95+ (I cant recall the Excel version)
4. 3800X tested on 29 July, 47.39
The gap between 2700X and 3800X is too large to be just a CPU upgrade.