for testing enviroment you should use a power supply with 12V and 5A. (normaly used the G4 without peak 3A)
Some 2,5" HDD´s are critical, you should look to the temperature specifications and shock specifications..
As sample, in a car like mine we have sometimes -20 degrees and i have not light shock absorbers in my car. (bumpers) is a heavy duty 4x4 car-.. ;-)
see picture, current when he do nothing...