Comment by lucb1e

Check your power-on hours:

    $ sudo smartctl -a /dev/sda | grep -e Power_On_Hours -e ^ID
    ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
      9 Power_On_Hours          0x0032   098   098   000    Old_age   Always       -       9743

Just looking at the raw value, it seems to be 9'743 hours in my case