Upgrading Memory
I am using 21.5inch 2011 Mid iMac 2.7HHz Intel iCore i5, my Mac memory is 2GB+2GB RAM 1333 MHz DDr3. I would like to upgrade my Mac to more than 8GB RAM, will it work if I bought 4+4GB RAM and fill with the empty slot adding with the current 2+2GB RAM, Or should purchase only new 2GB + 2GB.. Please advice.