The faster CPU and Optane 905P SSD makes a difference but the slowest factor is the Asus Rampage V Extreme. It has many features and that makes it post and boot slowly, even without memory training.
specs:
i7-5960X
32GB RAM
GTX 980 Ti
Samsung 850 EVO 2TB
Asus Rampage V Extreme
i9-9900KS
32GB RAM
RTX 2080 Ti
Intel Optane 905P
Gigabyte Z390 Aorus Master
