1 DVD, 2 different readings

Dear all,

I have two dvd drives, a Liteon SHW-1635S and a 16x8Dual MicroAdvantage DVD.

When i do a Nero scan on the same Verbatim 16x dvd on both of these drives, i get very different results. the liteon dvd gives over 5 PI failures, but the other drive gives no failures. The Microadvantage does not show PI failures or give a bottom graph. which reading do I accept as the most valid?

The second confusing thing is that i thought PI failures were bad, but when i scan the DVD using CD Check, the DVD comes up clean. Are PI failures synonmous with CRC values check in CD-check?

The third problem is that Nero speed disk gives very different results depending on the drive speed of the check. what drive speed should i use?

Hereto date i had been using CDCheck to verify that my DVD’s wouuld not hang and it was a reliable method as if i had no crc errors, my dvd would work fine. but now nero gives PI errors in the same dvd that cd check says is fine.

Can anyone help?

A number of questions here, I’ll see what I can answer.

  1. The Liteon is a reliable scanner, go with it’s results.

  2. CD Check is doing a bit by bit comparison of the data on the DVD. A scan checks the quality of the burn. It is possible, albeit not too likely, to have a perfect scan but have CD Check throw up errors because the data was transferred incorrectly.

  3. CD-DVD Speed - I think 4x is the speed for a liteon to scan at.

Hope that helps.

thanks timc.

If i assume correctly from your answer on #2, that for “bottom line” testing, cd check is the way to go to verify a DVD burn, as sometimes a perfect scan will not reveal data errors(?).

What would be the purpose of Nero CD DVD speed then?

your other responses were most helpful as well.
thanks again,

sorry Timc,
one other note. CD Check has two options, one is for “check” the other is for “Compare.” I am not doing the “compare” which i assume be what you thought in “bit by bit comparison,” unless i am mistaken?