Another 2011 15" MacBook Pro successfully repaired by replacing the GPU!pic.twitter.com/9ZD1I0y7p7
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Definitely a hardware issue. On a white MacBook though, I'd recommend you just get a new logic board. New boards for most white MacBook models go for less than $30 fully working.
eBay is the best place. Which specific MacBook model is it? (MacBook 1,1, 2,1, 3,1, etc..)
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