Find a used optiplex with a i5-4570 (100$) or similar, find a used gtx 770 for 76$, get a new 500W psu (35$), and a ssd(30$) and prob some more ram (40$ for 8gb)
and upgrade the PSU to this:
PCPartPicker part list / Price breakdown by merchant
Power Supply: Corsair - CXM (2015) 450 W 80+ Bronze Certified Semi-Modular ATX Power Supply ($19.99 @ Newegg) Total: $19.99 Prices include shipping, taxes, and discounts when available Generated by PCPartPicker 2018-11-24 21:34 EST-0500