How to determine PCB Fail

To all hdd guru.

I have some question about "how to determine PCB fail problem"
in case of " how can we know which IC / Chip controller that fail ". it's generally same to all brand of hdd (like maxtor, seagate, WD, Fujitsu, etc) ?
what tools we can using to find where is the fail IC/chip ?

p.s special to oldtech.

I have read your interesting explanation in this forum. can you share to me how can I determine which IC /Chip controller that fail in PCB ?
many thanks for the help

regards
Tony