I know it maybe sound stupid, but i dont know if mix colors can make a difference
White: http://www.crucial.com/ProductDisplay?urlRequestType=Base&catalogId=10151&categoryId=&productId=1274011&urlLangId=-1&langId=-1&top_category=&parent_category_rn=&storeId=10151
Gray: http://www.crucial.com/ProductDisplay?urlRequestType=Base&catalogId=10151&categoryId=&productId=1268505&urlLangId=-1&langId=-1&top_category=&parent_category_rn=&storeId=10151
Thanks
White: http://www.crucial.com/ProductDisplay?urlRequestType=Base&catalogId=10151&categoryId=&productId=1274011&urlLangId=-1&langId=-1&top_category=&parent_category_rn=&storeId=10151
Gray: http://www.crucial.com/ProductDisplay?urlRequestType=Base&catalogId=10151&categoryId=&productId=1268505&urlLangId=-1&langId=-1&top_category=&parent_category_rn=&storeId=10151
Thanks