HP Z840 Workstation 2x E5-2690 V4 2.60GHz 256GB Ram/ 1TB SSD/ No OS/ M2000 GPU | eBay
Refurbished: HP Z2 Mini G4 Workstation (Performance Unit) Intel Xeon E-2124G 3.4Ghz, 16GB DDR4 RAM, 256GB NVMe M.2 SSD, Quadro P600 4GB, USB Type C, Windows 10 Pro (Grade B) - Newegg.com