Hello All,

I have a few question about HDD Scan 3.3

When you do a surface test, what is the difference with Verify, Read, Erase, and Butterfly Read?

I tried only both Verify and Read. Both giving me different numbers and Verify is much faster. Does both Verify and Read can scan for bad sector? Which scan is much more accurate?

I assume the blue box marked "bad" is actually a "bad sector"?

Many Thanks =D

As far as I can see, your questions are answered on the HDDScan website, where the different test types and their behaviour are explained. Therefore to avoid me repeating things which are already written, I suggest you read this webpage:

http://hddscan.com/

If you still have questions after reading that information, then please explain your hardware configuration, the disk interface which is being used, any concerns about your equipment (i.e. why you are running tests) etc. etc., when you ask any further questions.

Hello Vulcan,

Thanks for the reply. I have already read the manual which included in the software b4 hand. Below is the quote on quote from the manual

"In Verify mode device reads block of data into internal buffer only and checks for consistency, there is no data transferring through interface connector. The program measures operation time for each block. The program tests blocks one by one from minimum to maximum.
In Read mode device reads block of data and transfers it thorough interface. The program reads block of data into temporary buffer and measures time of operation for each block. The program tests blocks one by one from minimum to maximum."

I just wanted to understand for two purpose:-
i) How to accurately check for bad sector
ii) How to check for other failure on HDD

My configuration setup are these two.

i) Various internal and external HDD wanted to be verify for bad sector
ii) 1 External Seagate(ST315000341AS) 1.5TB having a weird "clicking" sound problem. Disc still running but when the "click" sound got worse, movie played is slowdown or hang, until the click sound is gone.

Also, just want to clarify why Read is slower then Verify and which one will give me a more accurate bad sector readings?

Sorry people, I am not so technical on HDD matters, please help

Many Thanks.

Your earlier questions included information which was explained on that webpage which I linked previously - which is why I directed you to there. Here are some brief comments to your reply. All are IMHO; others may have different views.


(i) Use either Read or Verify - Verify will be faster (see below). However, if you don't have a backup of the data on that disk, then don't run a surface scan until you have a backup of the data.
(ii) That question is too vague for me to want to try answering.


The clicking typically indicates an internal disk problem. Backup the data (or clone the disk) ASAP, if the data is important to you, before this becomes a data recovery situation. Also collect and review the full SMART data (including raw values), to see if that gives confirmation about a disk problem.


Verify does not transfer the data across the interface; Read does transfer the data. This is explained on the webpage that I linked. Therefore Read will be slower than Verify, especially if the interface is slower than the disk's transfer speed (e.g. USB 2 interface). No difference between them in "bad sector" detection.

Hey Vulcan,

Thanks for the advice



Just one more Q to clarify my doubt, what is the purpose of Read to transfer the data across the the interface vs. Verify?

Many Thanks

You're welcome


Think about a normal PC. Usually the PC CPU needs to actually use the data from the disk. Therefore a PC uses the Read (and Write) commands for normal I/O. The Verify command is only used when the actual data from the disk is not needed. You can think about Verify as simply giving a pass/fail answer, about whether the data is readable (although the details can be a little more complicated).

Hi,

This may sound stupid..but i need help on it..

From HDD Scan, how can i check for my hard drive health? I've run the SMART Test, however only number 001 to 190 appears.

And also, may i know how is this erase mode works? All i know is that it will replace data but i do not know further details about it...