Could we assume that HDD is perfectly free from real physical caused bad sector if the report after write zero states zero bad sector? IF assume there is real phyiscal caused bad sectors, could we conclude as well that these bad sectors would also show even if after write zero?
I read it twice.. but I'm still not sure what your question is. What exactly do you mean, or are you asking?
I read from your articles about myths on the HDD. From there, I summarise that there are 2 types of Bad Sectors. One would be the physical damage on the platter itself in which these are bad sectors that can never be repaired. There is another type which is not damage of the HDD but something else. Question... Write Zero on the HDD and then check with command promt chkdsk g:/f and report shows 0 bad sectors. Does this mean tjhat there is no physical damage to the HDD? I mean no physical damage based on bad sectors.... Thanks
Sometimes it could be relocation of the bad sectors by using the spare sectors. So technically, the bad sectors are still there.
It may be, it may be not. After a low level format, bad sector disappears, but that doesn't mean there's no physical damage. The moment I see CRC error while accessing the HDD, I will discard the hard disk immediately. That's me.
Even a new hard disk drive can have defects on the platters. That's why they always do a low-level format and mark out the bad bits. They will also allocate a number of spare sectors for use as replacements when a sector goes bad. When you check a drive and it develops bad sectors, the OS will mark them out as bad. You can do a low-level format to replace them with spare sectors. However, physically the bad sectors are still there. They were just replaced "logically" with good, spare sectors. BTW, CRC errors can be caused by a bad cable.
Bah... all drives have bad sectors, you don't see it doesn't mean in not there. There is no 100% perfect media...
Hmm.. Sounds like a bad sector leh.. Maybe you should do a low-level format to "move" that sector out. But you are right.. once a drive starts developing such signs of failure, it's best to migrate to a new drive.