4GB Team High Performance Memory RAM Upgrade Single Stick For Lenovo ThinkPad T510 Series W500 Series Laptop. The Memory Kit comes with Life Time Warranty. at Amazon.com
Tutorial: Upgrading the Ram on a Lenovo or IBM Thinkpad Laptop (in 1080P!) - YouTube
OFFTEK 4GB Replacement Memory RAM Upgrade for IBM-Lenovo ThinkPad W500 (4058-xxx) (DDR3-8500) Laptop Memory at Amazon.com
Arch Memory 4GB 204-Pin DDR3 1066 MHz So-dimm RAM for Lenovo ThinkPad W500 4058 Series at Amazon.com