Years ago walmart used to sell video cards and memory, but I have not seen a video card or a memory chip in walmart in several years.
Just about everything walmart sells is low end and cheap. When people buy the stuff, it does not preform as expected when they get it home. Look at their desktops and laptops, they are usually in the less then $500 range.
I have often wondered how much training the people in electronics get. When I ask a questions, the eyes of the walmart employee glaze over like they have been eating donuts.
When I bought a video card from walmart in the past, it was usually for one of my kids computers, and I needed something in the low-mid range of performance.