what os can I use on a mid 2009 MB Pro with 4GB memory
Hi. I want to update my wife's MB Pro and would like to know how far up can go with Mac OS, Sierra, El Capitan. She has Lion now.
Thanks for your help.
MacBook Pro, macOS Sierra (10.12.4), 2.2 GHz. i7, 8 gigs. memory 128 SSD