install xp pro over win 98

[Guest]

when a drive is near to complete failure, there may be no symptoms

 

The hard drive guys were aware of this and in the 90's IDE hard drives adopted SMART (Self-Monitoring Analysis and Reporting Technology). For instance, if a drive runs low on spare cylinders, it can report this so the user has time to replace the drive before there is any data loss. The reporting has been implemented in OS's as early as Win98 and even some BIOS's check and report predictive failure everytime you power up.

 

Someone mentioned full formatting a floppy physically erases each sector. In my experience, this is not the case under Windows like it was under Dos. Windows does simply verifies if each sector is readable (lame because reformatting is beneficial on floppies to strengthen the signal of the sector id's). Of course if there was a density change, it would be forced to do a true format. Also note just overwriting old data with new is not necessarily safe to assume the old stuff is gone. Depending how sophisticated someone is, they can recover second, third and further generation old data. A government agency doing a study on this concluded the only way to conclusively erase the data is to destroy the media.

 

[Guest]

I suppose it is technically possible that the format program will check the target floppy, and if it's the same density as the user wants to format it to, just check if each sector is readable instead of doing a full format. However there would be no reason for this as touching each sector for a read is no faster than a track-level format. I contend (friendly contention, mind you ) that your observation is flawed and that under Windows formatting floppies is identical to the way it was under DOS (when not quick formatting). In fact, format on Windows 95/98/ME is a 16 bit program that just issues int13 BIOS calls -- in other words, it *IS* dos format.

 

But, you are right about the recoverability of old data. A "low level format" (really just means that new sector marks are written) of a floppy does not guarantee that old data is not recoverable. Sensitive equipment could recover data (the floppy drive in the machine cannot do this however). I believe the same is true for HDs.

[Guest]

Formatting a floppy is slower than verifying tracks for several reasons, primarly because it takes two passes (format+verify) vs just one (verify). There are no read after write heads on the drive so the format operation cannot detect bad sectors and requires the second pass to do this.

 

In the good old days of Dos, FORMAT.COM used BIOS INT 13 AH=05 to format tracks which is a hardware level format operation. In the modern windows world, they changed even the 16-bit FORMAT program not to use the format track any longer and it uses the other INT 13 function to verify only. This means anyone on any machine can fire up the built in debug utility and read all the old data! Granted they would have to piece together the files manually.

 

Also, the drive does more than write new sector marks on format, it applies write current index hole to index hole, writing the contents of each sector using a format fill character. This, like overwriting sectors with 0, will prevent ordinary systems from reading back any of the old data.

 

[Guest]

Yes, that would be function 4, verify sector. I don't have Windows installed here anywhere to verify your statement, but it sounds plausible.

 

BTW anyone who quotes int13 to me immediately gains my respect .

[Guest]

Me too

 

[BritTim]

Yes, of course you can check the SMART statistics. You can, even better, get the diagnostic utilities from the vendor whose drive you are using. But, in practice, almost nobody does. In my experience, BIOS checks on hard drive SMART statistics is fairly unusual. One issue here is that different drives use different SMART features (and the way they should be interpreted also varies) so it is not trivial for a BIOS to opimally handle all drives.