EliteBook 755 G4 Upgrade Questions

[Yebubbleman]

I have an HP EliteBook 755 G4 that I'm wanting to upgrade both the storage and RAM on.  I currently have a 256GB SSD and 8GB of RAM; I want to max out the RAM and get at least a 1TB SSD.  (The warranty on it JUST expired, so I feel less worried about potentially voiding the warranty with it.)  Given this, I have a couple of questions:

1. The model number of my EliteBook 755 G4 is 1FX49UT#ABA.  When I google it, I see sites telling me that it's a 256GB M.2 drive, but they're not specific as to whether it's an NVMe drive or a SATA drive.  I want my upgrade/replacement drive to be the same as what's already in there.  Is there an easy way to determine which I have installed without opening it up?  I'd ideally like to only open it up when I'm ready to upgrade things.

2. Where should I buy upgrade RAM from and what kind of RAM (a. from which vendor and b. which speed) should I buy?  I have historically used Crucial for my Asus, Apple, Dell, and Lenovo systems, but HP seems to use lower-speed DDR4 RAM than the rest of the industry on their machines (most are content using DDR4-2400, whereas HP has used DDR4-2133 on Intel systems and this HP seems to be using even lower-spec DDR4 for its RAM).  What I've done on my other HP machines (which are all Intel based and use DDR4-2133) is go to NewEgg and buy Corsair ValueSelect DDR4-2133 RAM to match the specifications of the original HP RAM.  However the BIOS fails to register the vendors of the RAM sticks (whereas it will identify the manufacturer of the OEM sticks).  This doesn't result in any kind of functional problems, but it leaves me feeling like I might not have picked out 100% compatible RAM.  What should I get for (a) this EliteBook 755 G4 to max it out to 16GB (that is the maximum here, right?) and (b) all of my other Intel based EliteBooks and desktop mini EliteDesks (that all seem to require DDR4-2133 RAM)?

[banhien]

@Yebubbleman 

HP EliteBook 755 G4is a series of many different models/products. Many models/products have M.2 SATA SSD, others have M.2 NVMe SSD and many others only have 2.5" HDD. Available options

               https://support.hp.com/au-en/document/c05350302

1. STORAGE: You can use Device Manager > Disk drives to see what it has now to buy a compatible one. For example, may machine has

          

2. RAM: The above link says it supports 16GB max using DDR4 PC4 – 1866 (Transfer rates up to 1866 MT/s). But finding 1866MHz RAM is hard. Actually RAM inside machine could be 2400MHz but is downgraded automatically to 1866MHz. You can use the following compatible RAM

               https://www.crucial.com/memory/ddr4/ct2k8g4sfs824a/ct10488931

Regards.