Advice? Knoppix 5.1.1 fails mid-boot from CD

**Harry Kuhman** · 04-29-2008, 04:42 AM

I use Nero, always verify, and you should always be able to get a verified burn. If it fails, the disc has a problem. Things to try include different brand of media, CDRW rather than CDR (avoids wasting more CDS but also using CDRW media changes the read gain at boot time that can help bypass some read errors), and burning on a different system (although if you have to do this it may indicate a CD drive problem that is also affecting the boot process). Also be sure that you are using 700 meg media; yes we have had long posts from a user who finally acknowledged that they were trying to burn the CD to 650 meg media.

**kwc** · 04-29-2008, 08:13 PM

Harry wrote:

I sure hope that you tested if you got a good download by the md5 checksum test (although if the disc works in another computer then the md5 sum is very likely good

No, I didn't run that. I don't understand it. I did get this from a Knoppix html download mirror listed on the official site and it did work on another computer. Still, can you direct me to a tutorial explaining how to use the md5 sum image to check it? I did download that, but have no clue as to how to use it.

Thanks,
kwc

**Harry Kuhman** · 04-29-2008, 08:52 PM

Originally Posted by kwc

No, I didn't run that. I don't understand it. ...

Answer #1

**kwc** · 05-03-2008, 01:51 AM

Solved. Finally.

Turns out a 1 gig ram card had failed. So programs/operating systems loading from CD (or harddrive) would start to load, start writing to/mapping one ram card and then when they moved to the second one (which has gone faulty) the computer would crash, reboot.

Had nothing to do with linux, knoppix, Windows. And only took me about 60 hours to figure out. And I only did that with the help of a very savvy tech who had a program that was able to stop the screen and let us read the blue-screen-of-death messages that were flashing before our eyes as the computer would reboot each time.

Popping out the defective memory immediately fixed the problem.

Thanks for all the help here.

Best,
kwc

**Harry Kuhman** · 05-03-2008, 02:17 AM

It might have been handy to know that if you boot the Knoppix disc and type in memtest at the boot prompt that you will run memtest86. That is talked about many places in the forums, in the wiki, and in the documentation that comes with a torrent download. We didn't get that far because we were still talking about things like did you confirm you had a good download with the md5 test. Glad that you got it resolved though.

**rubbertoe** · 05-03-2008, 10:44 PM

I was having a similar issue booting from various live CDs. I suspected the memory and ran memtest through 3 times and found no errors. I then decided to run it overnight, yet still no errors. Upon realizing I had some extra DIMMs laying around I swapped out the memory and voila! Frustrating to say the least. So the moral of this tail, memtest is a great tool yet don't rely on it 100% as with everything.