The fan connector is kinda loose in the socket on the GPU? Get a small tube of silicon goop and put a blob on it. The blob will dry and hold it, and will peel off easily when you need too. Put the blob on the connectore AFTER you connect it, it's just there to hold the connector in, not seal it.
Someone got a hot glue gun, used by hobby folks for decopauge? That would be even better. You can buy one with a few pieces of glue for like $10 at walmart in the hobby section. And it'll peel off.