For anyone that wants a cheap solution to stop the on going loud fan, just buy a SATA extension cable. This will not void your warranty at all
Don't get confused with micro-sata or slimline extension, its a different connecter.....Example, should have both connections type as one whole cable (one side female the other male... duh):
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Using this extension you would be able to place the HDD externally to the router, this will reduce heat build up within the router. HDD are normally fine running passive to room temperature anyway, just try to place the HDD securely to a flat surface...
Tested transfering data from the HDD...... *SILENT ROUTER*

P.S. can be tricky installing the male connector within the router