DVD boot

[ckamin]

mpn:

You did not say whether you tried the "knoppix nodma" cheatcode. It may have the solution for many optical drive issues, since some controllers need it enabled and others need it disabled to work correctly. If you are using Version 5.0.1, then it is enabled by default. Some prior versions were disabled and much earlier, enabled. It can cause slow reads and error messages.

Also the type of media can be an issue. Some drives will read DVD-R, OR DVD+R, and sometimes both. Trying a different media type might be the key also. I would look at the data/spec sheets for your optical drive to see what capabilities it has.

[Harry Kuhman]

Some prior versions were disabled and much earlier, enabled.

Actually, the history is disabled by default, then enabled by default, then "opps, that is causing way too many problems, let's disable it again", and now finally "hey, I forget why we disabled it, lets re-enable it".

Also the type of media can be an issue. Some drives will read DVD-R, OR DVD+R, and sometimes both. Trying a different media type might be the key also. I would look at the data/spec sheets for your optical drive to see what capabilities it has.

Good point, I had forgotten about trying the other polarity of media. But now that you mention it I would also try DVD/RW media if you have any, for two reasons. First, nothing is lost if it doesn't work. And second the difference in gain needed to read it sometimes corrects problems. I found this out years ago with CDRs and CR/RWs, I would have expected CDRWs to be even more picky, since the bit transistions are much less and it takes extra electronics to read them. But I had a drive that started flaking out on CDRs and eventually all it could read and write correctly was CR/RWs (it could still read pressed CD's), but it worked on CD/RW's fine until I retired it.

[ckamin]

Actually, the history is disabled by default, then enabled by default, then "opps, that is causing way too many problems, let's disable it again", and now finally "hey, I forget why we disabled it, lets re-enable it".

Harry, You are certainly right about it starting out as dma disabled by default. My memory needs periodic testing and it failed on that one. It's hard to remember past last month, let alone a few years ago. I have seen dma cause some very strange issues in numerous operating systems. I like the option in the Knoppix menu where you can enable or disable dma on certain drives. You can start up without dma and then enable dma on the hard drives selectively and leave the optical drive off or vice versa, depending on which devices are troublesome.

Good point about the RW media.