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I would not recommend buying non-Apple RAM, because that is not guaranteed to compatible with Mac. It also might void the warranty if the part causes a problem, and an Apple Genius didn't install the part. However, if you want to take a chance, I would Google 'macbook pro model XXXXX RAM' and then buy the cheapest new that you can find. Don't buy from places like eBay or online retailers that you have never hear of.
 
I can't say for sure, but from what I've read from these forums, it seems that any RAM that is DDR3 1066MHz, 204-pin SODIMM should work.

Many tend to recommend Crucial :p
 
I upgraded my 13 MBP with 4gb of Crucial RAM ( and a 500gb WD Scorpio Blue ) - no problems whatsoever.

I cant vouch for Kingston RAM but as far as i know as long as its the correct spec RAM it should work just fine. i've upgraded every Mac I've owned with crucial RAM and not had a problem , so i just stick with them.
 
I can't vouch for either Apple or non-Apple ram. I had 1GB in my white MacBook, and a few months after I upgraded to 4GB from Kinston (correct spec, etc.) my MacBook's logic board developed some problems near the ram slots. Not sure if they relate, but my new 15" MBP has 4GB of factory ram and is running great. Some sites like macsales.com sell ram that Apple uses, it will say factory original somewhere.
 
To be honest...

To be honest I would never buy Apple Ram as it's ridiculously expensive. I have never heard of anyone stating that Apple refused Apple care because they changed out the memory. The RAM is a user replaceable item. Keep the original to install for troubleshooting down the road or put original memory back in if you need to take to Apple for Apple care.

As for 3rd party RAM, no not all RAM modules work with Macs ass they are picky , and no not all manufactures guarantee to work with Mac.

I have been running Mac now for about 7 years and I have ALWAYS used Crucial in all my Macs which I still have everyone I have ever purchase (given to family members so they would final put there PC's to rest) about 6 of them. I have never ever ever had any of them (all running Crucial) give me problem with RAM.

There are other companies that work and guarantee to run with Mac but I can personally endorse Crucial and they guarantee it to work with your mac or full refund. Buy from Crucial or Newegg, both good. Also check with OWC macsales as they also guarantee all there memory with Mac.
 
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