Retail stores never support the products they sell directly. Anything you buy from a retail store, if you have problems, they direct you to the manufacturer of the product. If you bring something in, they send it off to the manufacturer for fixing.
Best Buy, Fry's, CompUSA, Micro Center, Circuit City, etc have tech departments that do only the most basic computer upgrades, and troubleshooting. Anything beyond the basics gets sent off to the manufacturer (which can easily take 2 weeks or more). Neither of them actually build anything they sell. If they have branded computers (in the case of CompUSA, and Micro Center), the computers are built by a 3rd party, and then CompUSA/Micro Center just put their badges on them.
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