You'll definitely be able to resell it.
One of my PCs is a laptop with an old 970m which is almost identical to a 670 in performance. Ran my Samsung Odyssey quite happily on that so with some downsampling you would be at comparable resolution. However... I can't recall if I even tried ED with it since the point of the laptop was to play ED whilst doing 2D grindy nonsense like mining whilst watching TV. Once you've got a headset you can start discovering all the tools, environments, apps and customisations etc.
The only downside is that, once you've used VR for awhile, you can't really go back to flat screen. It's like going back to radio after getting a TV.