"Fixed" or hidden bad sectors?

[jimnms]

I have an old 80GB Maxtor that wouldn't boot. I ran Seatools on it, and it found and fixed 24 errors. I thought or assumed they were bad sectors (it was late, and I was tired). Afterwards it booted into Windows and ran just fine. When I ran chkdsk, it reported "0 bytes in bad sectors." Does Seatools have a magical way of fixing bad sectors, or did it do something in the hardware to hide them from the OS?

I've already replaced the drive in the machine, but I'm experimenting with the Maxtor. I wiped it clean, deleted the partition and re-formatted it. I ran chkdsk, and it still shows 0 bad sectors. I ran a full scan with Seatools again and it didn't find any errors. How can I find out if the drive has bad sectors on it?

 

[tdg]

Bad sectors nowadays are usually detected by the drives controller before the the OS or a disk check program ever knows, the drive itself has spare sectors on it for this reason and remaps the logical sector to a new physical sector when it finds them, and then marks that bad physical sector as such so it will not be used in the future (even if the drive is zero'd-out, formatted, etc.) If Seatools itself found 24 bad sectors, it could mean the drive didn't catch them, or ran out of spare sectors to remap things to.