Question counting memory chips for compatibility?

[lada_]

brispuss provided some useful info back in 2015 re this issue of density of memory sticks, thanks sincerely! Your answers resolve a great deal of confusion over what to know in adding memory to my Dell XPS 8930.
I've received a possibly curious answer from crucial re compatibility of memory sticks and I would very much like to be certain this is vital info, or not, before I add my new memory stick.

I bought crucial, following instructions in another thread, that it is most compatible with my device. ✔
However, I did not grok that the 16GB I purchased would require some mental prowess re determining whether it is alright to use with my 8GB that came installed with the XPS 8930 last July. (I've adding memory to other computers in the past).

After some time clarifying the meaning of the crucial online support member's slightly cryptic replies, I finally got this answer: the number of chips on the back of my new memory stick need to be the same number as on the installed memory stick. 🤔

The manual also states "put the highest density module in bank 0". ✔
I also used crucial's application on their website to choose from the memory stick's compatible with my current computer. One does hope that app is accurate! ✔

Since the above mentioned thread dates 2015, I've no idea if anyone will catch my question. So I decided to post anew.
Essentially, I am 'asking' about that counting the number of chips on the back of the memory stick as useful data for this compatibilty of memory sticks? 👈

Thank you sincerely and respectfully.
lada_ 🙏

 

[lada_]

Followup:
I have learned a few things in the few minutes of 'checking one more thing' ...
Dell does not refer to a number 0 slot in the memory order.
Rather DIMM 1, 2, 3, 4 ....
I am waiting on a crucial tech support member to locate how slot 0 corresponds to Dell's labeling of the memory slots. She seems to be having difficulty.
So, my remainging question on this matter is:
High density (16GB) memory stick in DIMM 1? and lower density (8GB) memory stick in DIMM 2?
Thx, Loves!
lada_ from England🏴󠁧󠁢󠁥󠁮󠁧󠁿