I found an Amd Hd 7870 at Ebay (used) for $76 and a Gigabyte GT 1030 at Amazon (new) for $85. As you can see here (https://gpu.userbenchmark.com/Compare/Nvidia-GT-1030-vs-AMD-HD-7870/m283726vs2161), the AMD is much faster, but it is used. Which one should I buy. Also, if it matters, I will be using either a i3 2120 or a i5 2400.