Hooray, even in today's stupidly priced PC hardware market, filled with $600+ "value" graphics cards, options MIGHT exist for converting an old office clunker into something that's fun! This little Radeon Pro has current drivers, full DX12 support, 4GB of GDDR5, requires NO external power...and can be had, shipped to your door, for $30-40USD; I paid $31 total for this one!
I know, I know, someone's inevitably going to shout at me that I didn't actually test it in an office PC, but that can be done later; I wanted to make sure there was a 0% chance of a CPU bottleneck in the benchmarks. And let's be honest -- if I had used an HP or Dell with an i5-3470, people would just be shouting that I didn't use more powerful hardware to really stress it!
900p used throughout unless otherwise noted, because if you're converting an office clunker from 2014 you may also be using a 1600x900 monitor from 2014. And I wanted to save a surprise for later!