Added an SSD but can't save anything to it

I added a 1TB Team Group MP33 SSD to the PCIe slot of my MSI gaming desktop with the intention of saving games to that rather than using up room on my C: drive.

I'm sure I installed it correctly because it clearly shows up in my Device Manager as an option. [Can't attach the screenshot I took.] But it does not appear where I can actually save anything to it.