Cyclic Redundancy Error - any way around it?

[timsimon1]

Hello All,

I know that this has been discussed alot on this forum, but I had to make sure to see if there was anyone who could answer some specific questions.

I get this error a hell of a lot. Mostly is comes from when I try to backup copied discs. Now, I know that it's due to corrupt data from the copy, but it happens on original discs too.

The frustrating this is, that they will play fine on any player and sometimes the error comes in when backing is up to 99% complete! Bummer!

I just wanted to know if there is ANY way around this at all. Is it possible to rebuild the DVD or something like that. Or manually modify the code. I know that it gets really technical, but I'd appreciate any ideas that you guys have.

Thanks!!

Tim

[Buddy Casino]

Hi,
CRC errors occur when the DVD-ROM can't physically read the disc, or if there are errors during data-transmission through the IDE bus, but I suspect that it is your DVD-ROMs fault. :D
But let's first try to rule out the other possibilities.
Try to read the DVD in a friends drive or so. If he can read it, it is not the media's fault (which is at least possible, there are many crappy DVD-Rs out there, and many burners with bad firmware). Else check for scratches, finger-prints etc.
The reason why you get this error more often near the end of he DVD is that the media quality of DVD-Rs deteriorates towards the outer edge of the disc.
If your media is ok (no scratches etc.), try first checking your IDE cables, update drivers etc. Maybe you are using 40-pin IDE cables with UDMA-5/6 devices (only HDDs use that) on the same bus as your DVD-ROM. If so, try upgrading to 80-pin cables if you have HDDs at the same IDE connector, and check if your devices are jumpered correctly.
But honestly, I still think you have to get a new DVD-ROM, because usually, Windows will just fallback to lower DMA settings if the IDE bus is the problem. Also, the fact that you have more problems reading DVD-R supports that thesis, because these are more difficult to read because they reflect less light than original discs, which points to a weak read-performance of your DVD-ROM. If the error-rate goes too high, the CRC algorithm can't correct them anymore, thus producing a non-recoverable CRC error.

[timsimon1]

Thanks alot mate,

That's really useful stuff. Yeah, my DVD drive is actually quite old. It's actually a DVD-RW drive that came with the computer (Dell) about 1 - 2 years ago.

I guess I should invest in a more up-to-date DVD Rom drive which you suggest should solve most of the problems. In point of fact, I can recall a couple of occassions when I got the error and a friend of mine didn't.

Thanks for your help geez.

Tim