O Current Pending Sector Count
está causando o seu problema :
Current Pending Sector Count S.M.A.R.T. parameter is a critical parameter and indicates the current count of unstable sectors (waiting for remapping). The raw value of this attribute indicates the total number of sectors waiting for remapping. Later, when some of these sectors are read successfully, the value is decreased. If errors still occur when reading some sector, the hard drive will try to restore the data, transfer it to the reserved disk area (spare area) and mark this sector as remapped.
Então você tem 100 setores instáveis onde o HDD tenta ler os dados e armazenar os dados em outro lugar.
Degradation of this parameter may indicate imminent drive failure. Urgent data backup and hardware replacement is recommended.
Portanto, faça backup dos dados e substitua o HDD por um novo drive. O melhor é comprar um SSD mais rápido.