The lower memory slot on my 15'' PB just failed, so I am going to bring it in to the nearest Apple store. My question is should I remove the 3rd party RAM (which is from Crucial) in the upper slot and leave only the original Apple module in the lower slot. I heard that Apple repair people do not like 3rd party RAM. Can they really refuse repair when they see a 3rd party module, or I should be OK leaving the 3rd party module in? Thanks.