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Wirelessly posted (iPhone 3GS: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_3 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8J2 Safari/6533.18.5)

Since I'm on my iPhone, I will point you to www.macsales.com and check your model Mac and see what the RAM type is and compare it to your eBay selection you have there.
 
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