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I appreciate your frustration, but the issue is not quite what you appear to believe. While it is obviously a critical one if you affected by it, the incidence of the issue involving defective capacitors actually appears quite small, when the overall number of machines which potentially are affected by it is considered. Apple did offer a no-cost repair extension authorization which covered users for a period of 3 years from the original date of purchase of the machine, regardless of the warranty status of the particular unit. In your case, eligibility ceased on or immediately after August 26, 2008, based solely upon the purchase date you indicated.
There are alternatives available to logic board replacement, which are substantially less expensive than the $ 620.00 cost you were quoted. The board itself can be refurbished by
this company for $ 189.00, plus the cost of shipping your machine or the affected module for service. While this this may still be considered to expensive to you, it is appreciably less than the cost you were quoted for logic board replacement.
Although it is possible that you have both a defective logic board and defective power supply, that combination is the least likely of the set of outcomes: it is far more likely that you have a defective power supply alone, or a defective logic board alone. It would appear from what you are quoted that the service center personnel examining it believe that you have a defective logic board alone. Final determination of that situation can only be made by performing an actual inspection and test of your specific machine.
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