2013-06-17, 05:56
Atom D2700 supports a maximum of DDR3-1066 (anything higher will be downclock to 1066) and it also has one memory channel. 1 x 2GB is enough for OpenELEC. The Atom is single channel so 2 x 1GB or 1 x 2GB will not make a performance difference. I'd get 1 x 2GB and have a slot open to add one later if needed.
Source: http://ark.intel.com/products/59683/
Source: http://ark.intel.com/products/59683/