Notebook RAM

[Miki641]

Hi,

I want to buy RAM for this notebook, I would expand it to 16 GB, next to the original RAM.
HP 255 G7 Notebook PC
[Personal Information Removed]
Would that do?
Crucial RAM 8GB Notebook | DDR4, 2400MHz (CT8G4SFS824A)

[erico]

The currently installed memory module is 8GB CL19 IRx8 DDR4-2666 Mhz 

The crucial memory module is DDR4 2400MHz PC4-19200 (PC4-2400T) CL17 SODIMM 1Rx8 1.2V Non-ECC

Do you notice the differences between them?

The upgrade might only see one of the memory modules. That makes the Crucial module you asked about a gamble.

You would have a better chance of the upgrade working as expected if you removed the installed module  and installed a pair of the crucial memory modules 

[Miki641]

Thanks, 

The currently installed memory module is not this either, but: Samsung DDR4 2400 MHz

How can you determine the exact type and detailed properties of the existing RAM?

[erico]

There are two things that are problematic about the memory module you asked about.

The first is that the CL (CAS Latency) is not identical to the installed memory. CL is a  primary memory timing parameter.

The second is that the crucial memory module runs at a lower speed than the installed memory.

That means that the upgrade with the module  could be a problem. There does exist the chance that only one of the modules will be recognized as being present by the OS when installed because of the difference in  CL (CAS latency).

The installed module with the HP part number is DDR4-2666. Install a slower module and the BIOS will downclock it to 2400MHz. I know that because I looked up the parts that are in your specific laptop in HP's PartSurfer utilty. I used the information you provided in order to do that.

Reference

https://www.google.com/search?client=firefox-b-1-d&sca_esv=19239ae0a447a3b4&sxsrf=ACQVn0_ksAse8fus84...

I hope that is easier to understand. Understanding primary and secondary memory parameters will involve a bit of reading on your part on memory upgrading. Upgrading  memory should be done with identical compatible modules for successful upgrades the first time.

[Miki641]

Thanks for the reply!
How can you find out the precise and detailed data of the installed memory? I also looked for the CL number, but I couldn't find it. On HP's website it says:
8 GB DDR4-2400 SDRAM (1 x 8 GB) Up to 2400 MT/s transfer speed.
So the speed is the same, or did HP write it wrong on the product page?
That's why I chose Crucial RAM, because the values are similar, but I don't know the CL value for the installed RAM.

[erico]

I did some research using keyword formulation in Google and the HP Part number. 

Not all of HP's marketing information is correct.

HP's part number information, on the other hand, is generally quite accurate.

HP Service Engineers use it for part information.

When researching memory I tend to look up both Kingston Memory and Crucial Memory.

Kingston Memory website provides even more information than Crucial's. 

Kingston's memory is also  used  as OEM in some HP products when they are assembled at the factory. 

[Miki641]

I typed this command line, cmd, enter:

"wmic memorychip get devicelocator, capacity, speed, memorytype", enter, and here it says 2400 MHz.

Was this checked by the computer diagnostically? Then this will be the exact value, but I was completely unsure.

I think the sure thing is that I will take the notebook apart and look at the type, I hope it can be identified.

And it also says that it can be expanded up to 64 GB.

[erico · Accepted solution]

You can believe that if you want or take the word of HP, Kingston Memory and Crucial Memory.

That is up to you and the loss of any funds and/or disappointment will be your own responsibility.

Here we tend to always try to err on the safe side so as not to cause a member unnecessarily spend their money of damage their HP products.  That is, if I remember correctly, in the HP forum rules of participation.

[Miki641]

Thanks for the advice, I decided to take apart the laptop and check the RAM, that's for sure.

Your idea is good, that two identical ones should be put in, so either I get one exactly the same as the existing one, or I buy two identical new ones.
Sorry for the language errors, I'm using Google Translate!

Miklós,from Hungary

[Miki641]

I'll report the result later, I'm already very curious because of the contradictory data. I just checked with two RAM diagnostic software, CL=17 for both. HP Parts wrote 19 on the current Samsung RAM.


It hasn't been in service yet, I bought a new laptop, theoretically they couldn't replace it.