ProBook 440 G3 : Add M2 SSD if SATA-SSD is already installed ?

[Robbsen]

Hello, HP Crew.
I just bought the used model 440 G3 and there is already a SSD drive inside, easily attached to the SATA port, as always.
The OS is installed on this.

Because I want to get maximum performance out of my new lap, I studied a bit about the possible configurations.
Then I read some of the posts, and...

...Huffer  said, that the M2 port would take 2 different forms of cards. Most interesting is the B2 here.
And additionally Huffer  said, that the internal soldering will guide the wires to either PCIe or SATA ports available on the motherboard. 

Ok, then I studied a bit, and saw, that the already built in SSD can make its 600 as we know it from SATA3.

So, no my assumption:

If I would buy an M2 SSD card, I think, that, mainly due to the protocoll ( AHCI ) I would,  gain no benefit, if that M2 port internally is NOT able to operate in NVME protocol. 


A) Are my assumptions correct ?
B) If not, can You correct them where I am wrong ?
C) If they are right, maybe You could kindly just confirm: There would be no performance boost, if adding  another M2 SSD over the existing SATA SSD.

Thx in advance.

[Huffer · Accepted solution]

You pretty much have got it right or at least close enough. Here is the Service Manual:

Manual 

M.2 slot is SATA only. Its not that the internal wiring leads to an existing port its how the M.2 slot is connected to the processor. NVME runs directly to the processor and SATA runs through a peripheral bus. Effect is the same. A SATA M.2 performs no faster than a 2.5 inch SATA SSD so nothing to be gained by going with a SATA M.2 if you already have a 2.5 inch SATA SSD.

Post back with any more questions and please accept as solution if this is the info you needed. 

[Robbsen]

Thanks a lot.