A GTX 1060 3gb would be faster and with less noise, heat and power consumption. If you can't find a 1060 in your price range, a 1050ti will do in a pinch until the next generation of video cards becomes widely available. The problem with used AMD cards is their compute performance is generally better than Nvidia, so a lot of people used them in mining rigs where they ran the hell out of them 24/7, but don't expect anybody selling one to actually tell you that. GTX 10 cards have so much better gaming performance than anything that came before or anything that AMD was selling at the time, that it is hard to recommend anything other than a used Pascal card if gaming is your intended use.
Some modern games also don't run well on cards as old as R9. You have to remember that the R9 280X is actually the HD7970 Gigahertz Edition in disguise, so it's even more outdated than it's release date would seem to imply.