A quick note for anyone reading this thread: Hard Drive critical temp ratings are taken in a non-operating state. If your drive is running at any where near 255degC you may want to purchase a fire extingusher. 255degC=491degF. 85degC is also what I would consider overtemp. Most drives that I've worked with are rated at 50-60degC max operating temperature. Drive temperature specifications can normally be downloaded from the manufacturers website.