Battery life of laptop when NVMe SSD is added to a stock 2.5" HDD?

[cbn]

For the sake of argument lets assume the laptop is a 15.6" with a 15W processor.

Storage:

1TB 2.5" 5400 rpm HDD

vs.

120GB/128GB NVMe SSD + 1TB 2.5" 5400 rpm HDD

vs.

240GB/256GB NVMe + 1TB 2.5" 5400 rpm HDD


In general, do you think Battery life would improve or decrease?

Hard drive idling vs. spun down (ie. heads parked).

 

[cbn]

According to this thread (from 2013) a 2.5" Western Digital Blue mobile drive does spin down regardless of the power setting the user selected in Windows:

https://forums.anandtech.com/thread...-ignore-power-settings-and-spin-down.2335497/

I just bought a 2.5" WD Blue wd10jpvx as a second internal drive in my laptop, and even though Windows power settings set the hdd's to never spin down, this WD Blue still spins down after about a minute and a half.

With that mentioned, do the modern Seagate, Toshiba, and Western Digital 2.5" HDDs have this same behavior?

Has Windows Power management changed?