HP ProOne Core i5 (4th Gen) (4 GB DDR3/500 GB/Free DOS/19.5 Inch Screen/ProOne 400 G1) - HP : Flipkart.com
Open Box: HP All-in-One Computer ProOne 400 G2 (Y7B25U8#ABA) Intel Core i5 6th Gen 6500 (3.20GHz) 8 GB 128 GB SSD 20" Windows 10 Pro 64-Bit - Newegg.com
HP ProOne 400 G1 AiO Intel Core i5-4590T 2.00 GHz 8GB RAM 500gb hdd No OS | eBay
HP ProOne 400 G2 20in Non-Touch AIO i5-6500 3.20GHz 4GB RAM No AC Adap
HP Proone 400 G3 20' No Touch Core i5-7500t 2.70Ghz 8GB 256GB DVDRW WIFI W/AC | eBay
Open Box: HP ProOne 400 G1 All-in-One Intel Core i5 4590T (2.0 GHz) 4 GB DDR3 500 GB HDD Windows 7 Professional 64-Bit (available through downgrade rights from Windows 8.1 Pro) - Newegg.com