Notebook Hardware and Upgrade Questions

Hello!

This is my last chance of finding some information regarding the issue I'm experiencing:

The Notebook I'm using is a HP ProBook 430 G5 (2VQ01ES#ABD). I bought it in 11/2017. I originally wanted to contact the HP customer support, which is obviously not possible as the warranty expired just three months ago. I really don't appreciate that you can't even get any official help by HP as soon as the warranty is over, especially as this problem is not warranty-related and just a usual technical request.

Further I have very little detailed information about the notebook itself, there is no specification table, manual or anything else remaining from HP online, at least that is what I experienced crawling through the web for the past two hours. Just some local shop pages listing the specs coarsely, not assured they are correct. So if someone could supply me with a data sheet or similar by HP, especially listing the RAM specs and requirements for the notebook, I'd already appreciate that greatly.

However, focus on my issue:
As the Notebook is shipped with a single module supplying 4GB of RAM, I experienced to use almost all of it during normal use, resulting in slowing down significantly with rising up time. This is why I wanted to upgrade to 2x8GB from Kingston, in detail the DDR4-2400 SO-DIMM Kit, serial number HX424S14IB2K2/16. Here's a link to the according data sheet from Kingston: https://www.kingston.com/dataSheets/HX424S14IB2K2_16.pdf

As far as I was able to research, the specs of the upgraded RAM are the same in terms of clock, latency is a little bit lower compared to stock of course. The Notebook is able to handle up to 32GB maximum according to multiple sources. The RAM module which is in there stock is a SAMSUNG 4GB module, serial number M471A5244CB0-CRC, also DDR4-2400. Information can be found on https://www.samsung.com/semiconductor/dram/module/M471A5244CB0-CRC/

The problem I experienced is the Notebook won't boot with the new RAM module(s). I tried all combinations of using one memory slot or the other and using both as intended, also cleaning and re-mounting the modules multiple times, the machine each time only gave me beeping sounds and blinking lights on the keyboard (can't remember the sequence exactly, but i googled it and it said 'Problem with hardware' - that's the kind of dedication to detaiI I like to see when trouble-shooting. 😄
However, if i put the OEM module in back again, it starts and works fine.

As I'm not an IT technician but have a lot of background in informatics, I also updated the BIOS as I took a guess on that to cause the issue. This resulted in getting rid of the beeping during the faulty booting attempts, but it stayed with attempts, the keyboard was blinking the same error message as before, only silently this time. I again tried all configurations of RAM.
Still working fine with the OEM RAM, not working with the Kingston kit.

Is there a general cause to problems like that? Do they occur regularly?
Are there modules that just don't work with some other mainboards? (Which I'd definitely call a fail in terms of technical standardization, especially nowadays.)
Did I oversee something crucial when buying the Kingston kit?
Where can I get information on which modules definitely work with my ProBook?

Thank you in advance!

Best regards,
Florian