Amazon.com : Lenovo ThinkCentre M73 10AY001RUS Tiny Desktop (2.9GHz Intel Core i3-4130T Processor, 4 GB RAM, 500 GB Hard Drive, No Optical Drive, Windows 7 Pro 64-bit) Black (Discontinued by Manufacturer) :
Amazon.com: New Genuine Lenovo Thinkcentre M73 Motherboard 03T7169 : Electronics
How to upgrade RAM in your Lenovo ThinkCentre M720q Tiny | Windows Central
Barebone Chassis - Lenovo ThinkCentre M73 Tiny Intel i3 i5 i7 4th Gen Mini Micro | eBay
lenovo ThinkCentre M73 SFF Small Form Factor Business Desktop Computer, Intel Dual-Core i3-4130 3.4GHz, 8GB RAM, 500GB HDD, USB 3.0, WiFi, DVD, Windows 10 Professional (Renewed) - Walmart.com