All - First results of my testing of Nomai disks
I'd like to preface this post by saying that I do believe that Nomai clearly wants the press to report that their disks work just like real Zip disks work. I also believe that casual testing by reporters is unlikely to uncover any serious defects in the disks Nomai is sending out; disk which certainly have been pre-tested before being placed in the hands of the computer trade press.
I tested two Zip disks and two Nomai disks in the same way, and my conclusion is that the Nomai disks are inferior in quality, and one of them quite possibly has fouled the heads of one of my Zip drives. I should point out that I have only done the most serious torture test on one of the two XHD disks I was sent. Details follow.
The Nomai disks did work in all three of the Zip drives I tried them in, including the Zip Plus, on SCSI internal and one ATAPI internal. They were accepted by the drives, formatting proceeded without incident, and data could be written to them and read back by the system.
Any reporter who does only this much testing might conclude that there is no difference between the Iomega Zip disks and the Nomai XHD disks. I would consider this to be a very casual form of testing.
I do not have a laboratory with large numbers of drives to do the extremely rigorous testing which this situation demands. I do have a utility which does continuous writes/reads/compares to the entire surface of a disk and keeps track of errors and reallocated sectors.
I used this utility first to test two different Zip disks. After 10 hours of testing on each disk, there were no errors and no reallocated sectors.
I then tested one of the XHD disks in the same way. After 10 hours of testing, there were no errors but there were two reallocated sectors. This means that data written to a specific place on the disk could not be read back accurately, so those places were marked as "bad" which tells the system not to try to use those areas to store data.
Following this test, I decided to check to see if the drive might behave differently with an Iomega Zip disk. In a bit over an hour of testing, there were still no errors and no reallocated blocks. However, I noticed that the drive was resetting the heads occasionally during the read/compare process, which could indicate that the heads have some residue on them causing them to have to retry a read.
Since I do not have special equipment to check the heads for residue, I cannot confirm that this is the problem.
I should note that this particular drive, the SCSI internal model, is used heavily by my wife, and has never, in my experience or hers, had this problem before.
Unfortunately, since my wife does need to use the drive to do her work, and since she also needs to use her computer, I have had to suspend testing for now.
- Allen |
