Does iMac 5k 2019 support Samsung 860 QVO as a SATA drive?

Sure you can replace (or install a new) your current HD with an SSD. I do wonder if that is the ideal setup. Depending on what your needs are, ther’re maybe better options.

I mostly focus on putting in as large as I can PCIe/NVMe blade drives into the system if its going to be a single drive setup.

For most people a HDD or SSHD for the data drive is the next direction. If higher speeds are needed then I jump directly to an external Thunderbolt drive as being the best option as SATA III (6.0 Gb/s) is much slower than what you can achieve externally!

Then there is the not putting all of your eggs into one basket thinking, While its nice to have a sleek system with everything inside there is the risk of getting access to ones data when things go wrong. Unless you are religious with a good backup solution that you verify yearly you could put your self in a bad place very easily.

You will need a 2.5” to 3.5” adapter frame, and if the HDD is not present, you’ll need the HD SATA/Power cable assembly.