OFFTEK 16GB Replacement Memory RAM Upgrade for Dell PowerEdge T420 (DDR3-12800 - Reg) Server Memory/Workstation Memory at Amazon.com
Upgraded the twins today. T420 got 16gb ram and a sled battery. 9cell + sled = 17hrs battery life. T480 got an extra 16gb of ram, up to 32gb. Happy with the
Lenovo thinkpad T420
CMS 8GB (1X8GB) DDR3 10600 1333MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Lenovo® Thinkpad T420 4177, 4178, 4180, 4236 Series - A14 at Amazon.com
16GB KIT (2 x 8GB) for IBM Lenovo ThinkPad T Series T420 T420i T420s T520 T520i. SO-DIMM DDR3 Non-ECC PC3-10600 1333MHz RAM Memory. Genuine A-Tech Brand. at Amazon.com
Lenovo ThinkPad T420 14.1 Inch Laptop i5 2.50 GHz 8GB 128 GB HDD Windows 10 Pro (Used) - Walmart.com