I fixed my friends Wii by re-applying Artic Silver 5 on the Gpu . The ones thats added on the Wii basically sucks almost like a DBl Sided Tape. Once Applied let it settle for a good 72 hours w/light game play. Once fully settled Good as new. Depends how bad your GPU is and most cases it should be fine. Heres a link and which you can buy @ your local PC store ...
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