upgrading compaq 6720s

[crystal127]

I have a Compaq 6720s and I am trying to upgrade it what is the best hard drive to purchase for it that would be compatible

[itsmyname]

@crystal127 -- is this your computer: HP Compaq 6720s Notebook PC Specifications | HP® Customer Support

It must be quite old -- originally shipped with Windows XP or Windows Vista, and a maximum of 4 GB of RAM, a 5400 RPM disk-drive, and only a 10/100 (not a 10/100/1000) network adapter.

The motherboard probably supports only "SATA 1" speed (1.5 Mbits/second), not "SATA 2" (3.0 Mbits/second), nr "SATA 3" (6.0 Mbits/second).  So, while any SSD can replace your current disk-drive, you won't get the full advantage of the "SATA 3" transfer-rates that the SSD is capable of. The lack of "rotational delay" in a SSD will somewhat improve the input/output transfer rates.

I think that you should keep your basic "appliance" computer as is (word-processing, E-mail) and not spend any money trying to "upgrade" it.  Save your money, until you can afford a new computer, with Windows 11 pre-installed.