Originally Posted by Ruslan
Yeah, those Diag utils use some parts of that hidden area in their work - like:
1. Firmware version
2. Serial number
3. Model number
All of these are located in mentioned configuration sector.
4. S.M.A.R.T. table status - some of utils can read it and translate into understandable terms.
5. Defect list table - none of Diag utils made by manufacturer will show you actual number of defects found on surface... :)
For WD Defect Table consist of two parts - P-list and G-list...
P-list has listed defects found during sertification test at the factory - and fixed by manufacturer. Ideally should be empty - but it never happens...
G-list shows grown defects found (and fixed) by using Diag utilities... Originally empty as it comes from manufacturer... Modern drives have so-called auto-reallocate mechanism (usually enabled by default). It means what any found (by drive itself) defects will be fixed without notifying you and substitute sector from the drive's reserve zone will be placed instead of defective one.
Defective sector's number will be placed into G-list.You will not notice any changes as long as there is still place for defective sectors in G-List... But in SMART (if enabled) you will see increased number of reallocated sectors...
Returned drives (Factory-refurbished) are generally those with fixed bad sectors or replaced electronics... So, replaced under warranty drive will be one of these, "tested and re-certified" drives...
Some of third-party diag utils can look inside Defect table - like MHDD v2.90 (works for IBM drives only)... Or HDDSpeed - for Quantum drives...
Now imagine this - if any of and-users can see that defect table right away and say - hey, my HDD is having a lot bad sectors! WTF is going on?! I want defect-free drive! Like any of us,though... ;)
Sorry guys, but that's almost impossible because of modern technology :( - every hard drive has bad sectors! But they are fixed by manufacturers...
And they are avoiding any potential problems by using any possible methods... including hiding sensitive info from us...