In the case I have installed a Samsung hard drive with 1TB and 5400 U / min. The housing is made of aluminum so I thought that the hard disk mechanical contact with the ALU housing but which proved to be wrong during installation. The hard disk sits on a plastic sled without any thermal contact the ALU housing. Therefore, the HD-temperature after a few hours of operation at about 43GrdC. For better cooling I will therefore drill holes in the aluminum housing.