I have little doubt right now the best price/performance is
http://www.ebay.com/itm/NEW-HP-MP9-G...oAAOSwImRYG-zD this auction.
Skylake quad core i5, 8GB RAM, 256GB SSD for 325 bucks -- the motherboard, the chassis and the power is almost free at that price.
As for people praising NVMe: you will realize that in real life desktop usage NVMe provides next to none advantage to a SATA drive. Benchmarks, sure, but nothing that you'd actually
feel.