SSD and SSHD together

[THE_freakydesig]

As we all know that the *hp pavilion x360 14-ba073tx* comes with 1tb Seagate SSHD. But I think it's time to upgrade my storage space.  I wish to add a SSD in addition to the preinstalled SSHD together.  Please suggest me with suitable configurations and devices.

[Huffer]

There is an M.2 slot but bad news is that its on the backside of the motherboard so requires extensive disassembly. Post back if you want to proceed anyway. 

[THE_freakydesig]

Are you saying I can upgrade with a M.2 SSD in my laptop particularly x360 14-ba073tx?

If yes what is the maximum capacity of memory I can install there.

[Huffer]

Yes subject to what I said above. There are M.2 SSDs available widely at up to 2 TB capacity. There is an M.2 slot on the backside of the motherboard of your laptop. 

[THE_freakydesig]

If I choose the option to go ahead and already having a 1TB SSHD what is the maximum capacity of SSD would my system support?

[Huffer]

Here is your Service Manual:

Manual

Your particular model can only use SATA M.2 SSDs, not the faster NVME kind. There is no capacity limit imposed by the hardware. You can install as large a capacity SATA M.2 SSD as you can find and I have seen 1 and 2 TB models and I think there may be 4 TB ones out there just very hard to find.. 

The back of the motherboard looks like this:

M.2 slot circled in red.

https://www.ebay.com/itm/Samsung-860-EVO-2TB-M-2-SATA-Internal-SSD-MZ-N6E2T0BW/264323943129?epid=150...

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