Hello forum,
today I used the HDDscan 2.8 software for testing several drives.

The first question which came up is what the difference might be between the verify and read modes. I only noted that read mode takes much longer than the verify mode, but I cannot find any help or FAQ entry which explains that.

Then I noted that the software is probably using the real time clock absolute values and not calculating time differences correctly. For example, when scanning an external USB drive the measured times depend on the activity of the other hard disks in the system. Do a copy of a large file or try surfing the internet while the HDDscan runs, that will greatly distort the results.

The program even miscalculates the measured times when switching between it's own MAP display and GRAPH display. The checkerboard pattern on the MAP obviously takes more CPU time than upgrading a few pixels on the GRAPH and the graph moves up a few millimeters when in GRAPH mode.

It is clear that the HDDSCAN suffers from internal inconsistencies and is not useable as a test and measurement tool in it's present condition. Hopefully future versions will be improved.

Regards,
Helmut Wabnig

Verify mode is using read verify command
Read mode is using Read command

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SAN, NAS, RAID, Server, and HDD Data Recovery.

I also notice that the speed is significantly slower when using "Read" mode rather than "Verify" mode.
It seems that it does not make sense since someone replied that for "Verify" mode, the program will "Read" and "Verify" but
if will only "Read" in "Read" mode.

I would like to know the turth.
Thank you

It looks like you don't understand what you talking about
Please download ATA standard from t13.org and read it, that should answer you questions

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SAN, NAS, RAID, Server, and HDD Data Recovery.

HDDScan 3.0 has been released
You can download it here - http://hddscan.com/

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SAN, NAS, RAID, Server, and HDD Data Recovery.

HDDScan 3.1 has been released
You can download it here - http://hddscan.com/

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SAN, NAS, RAID, Server, and HDD Data Recovery.