https://en.wikibooks.org/wiki/Minimizing_Hard_Disk_Drive_Failure_and_Da…
"Hard drives with average temperatures below 27 °C had a failure rate worse than hard drives with the highest reported average temperature of 50 °C"
"It is recommended that the operating temperature of a drive not steadily exceed 47 °C, as this may disproportionately reduce its life. This, however, may not be feasible in laptops."