Per Mactracker, your (2008?) MBP 4.1 can take 6GB RAM, and if you're going to upgrade to Yosemite, my advise is to max out. (I'm surprised that you've been happy running Snowy with only 2GB.)

Edit: joemikeb's suggestion (in post #32953) that you use a cloning app rather than Time Machine is worth exploring.

Last edited by artie505; 02/07/15 01:03 AM.
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