Thanks for the input.  Perhaps Ethereum might be a better choice.  As for the power supply, I've also got an extra EVGA 1300 G2, so it's probably better to have each handle 1/2 the load.  I don't see $100 for a motherboard as too expensive.  So my question would be for mining Ethereum, is it CPU intensive?  Is a i5 8400 good or is it better to go higher or lower?