2010 Core 2.4 GHz Mac mini RAM Upgrade
From Support Apple's page:

http://support.apple.com/kb/HT4223

Mac mini (Early 2009), Mac mini (Late 2009), and Mac mini (Mid 2010) computers have two internal memory slots. These slots accept a standard PC3-8500 DDR3 204-pin SO-DIMMs (Small Outline DIMM) with the following specifications:


PC3-8500 DDR3
unbuffered
non-parity
204-pin module
1066 MHz


DIMMs with the following features will not work with these Mac mini models:


registers or buffers
PLLs
ECC
parity
EDO RAM