Toshiba's nothebook HDD is not reliable.

I have serviced 4 laptops in my office, all CLEVO notebooks from Taiwan but all using Toshiba HDDs.
All of them are between 3 - 5 years old.

1 HDD totally cannot detect.
1 HDD have plenty of bad sectors.
1 HDD have no bad sectors, but HDD controller failure while read/write causing slow loading and response, almost like HDD frozen.

The worst thing is Toshiba do not have any diagnostic utillity for their HDDs!