How to find out timings of RAM memory spare parts? How to combine DDR4 memories?

[asg45sdg4d85h4]

https://partsurfer.hp.com/media/photos/L46598-002.jpg

1. How do I determine timing (summarized - e.g. Kingston mentioned beneath or non-summarized) of this SODIMM RAM in HP ProBook 455 G7?
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Item:

-N/A-

L46598-002 SKO-MEM 8GB 3200MHz 1.2v DDR4 SHARED   B -N/A- NULL

https://partsurfer.hp.com/Search.aspx?searchText=12X19EA

This original HP RAM part costs approx. 130 €.
2. Why is it (HP original RAM for 130€) so expensive compared to Kingston 3200MHz 8 GB DDR4 (around 36 € => Kingston: 8GB DDR4-3200MHz SO-DIMM CL22 noECC 1,20V)?

3. Will there be any performance downgrade when using not original RAM memory with different timings, because AMD CPUs tend to be more RAM specific (Infinity Fabric?) - at least desktop CPUs?
4. Does HP original 8GB RAM support ECC?

Thank you in advance.

[Paul_Tikkanen]

Hi:

Your notebook does not support ECC memory.

I would buy Crucial memory since they guarantee compatibility...

https://www.crucial.com/compatible-upgrade-for/hp---compaq/probook-455-g7

Find the part number you are interested in and change the country flag at the top of the page to the EU, enter the part number in the search window, and find a seller.

[asg45sdg4d85h4]

Thank you (kiitos) so much for your response.
I will seek this, thank you: Crucial SO-DIMM 8GB DDR4 3200 MHz CL22 part: CT8G4SFRA32A

Please, if you were so kind to answer my additional question(s):

HP ProBook 12x19ea maintenance guide screenshot:

Memory Configs

1. Is it theoretically possible that combination of original stock 8GB DDR4 will work with 16 GB Corsair 3200 MHz DDR4 (e.g. Crucial Part: CT16G4SFRA32A), because 12GB(8+4) definitely works? It is not listed, but it does not mean it can't work?
2. What about single rank or dual rank (there are 2 types in your link) when buying additional RAM to stock HP ProBook RAM? Which one do you prefer (in terms of performance, durability...) and probably why?

EDIT: After reading this, there is another parameter x8 or x4 (fortunately, at your link, there is only one possibility to choose).

https://community.acer.com/en/discussion/534035/do-i-have-to-use-single-rank-x8-or-x16  :

(Screenshot: https://pasteboard.co/JA4iXLC.png) 

Thank you so much for your reply.
Sources (I read):
https://www.crucial.com/support/articles-faq-memory/what-is-a-memory-rank
https://pcpartpicker.com/forums/topic/167242-what-do-these-numbers-indicate-on-ram-pc4-25600-vs-pc4-...