CMS 8GB (2X4GB) DDR3 10600 1333MHZ Non ECC SODIMM Memory Ram Upgrade Compatible with Asus/Asmobile® K52F Series K52F-Sx071; K52F-Sx071V; K52F-Sx139X - A29 at Amazon.com
4GB Team High Performance Memory RAM Upgrade Single Stick For ASUS K52DR K52F K52JB Laptop. The Memory Kit comes with Life Time Warranty. at Amazon .com
A-Tech 8GB KIT (2 x 4GB) For Asus K Notebook Series K40IE K42DE K42DR K42DY K42F K42JA K42JB K42JC K42JE K42JK K42JP K42JR K42JV K42JY K42JZ K42N K50I. SO-DIMM DDR3 NON-ECC PC3-8500