Q: I'd like to uprgade the RAM on my 4GB on my Mid 2010 iMac. It has an intel i3 processor running at 3.06GHz. Is it supported by apple and what is the maximum upgrade?

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It's supported. Your Mid 2010 iMac supports officially 16 GB of memory, but you can use 32 GB of memory. Read > http://support.apple.com/kb/HT1423?viewlocale=en_US#1

You can buy memory in OWC or Crucial > http://eshop.macsales.com/shop/memory/iMac/2010/DDR3_21.5_27 Then, use the first page I gave you if you need help to install the memory

According to the EveryMac website (which is more thorough), the 2010, i3 models only support 16 GBs of RAM.

The 2010, i5 and i7 model iMacs support up to 32 GBs of RAM.