This is very helpful, thank you! Yeah the CPU is just as old as the graphics card. It's an AMD FX-Series chip if that tells you anything (I'll have to check dxdiag later to be more accurate). I don't know much about bottlenecks, but I figured that might be an issue.
The specific model will be useful, but any FX series chip is going to be a bottleneck to a modern graphics card. I wouldn't recommend anything better than a GTX 1050 Ti or RX 570.