Bought this mystery M.2 Artix 7 devboard from ali, "XC7A50T-IO". It's also available in 35T and 200T flavors. I had to pay like $10 for someone to download the developer resources off Baidu Pan which was linked on an image. So far the device works, the docs are not great but adequate, although it's all in chinese. I'd say it's 100% worth it for the price.