Have you already tried to download the offcial version ? (not coming from a torrent source).
http://www.knopper.net/knoppix-mirrors/
I have tried to boot 3.4 5-17-04 several times with two separate burns on my old Gateway Solo 2500 laptop (PII 128m, 6g). Previous versions of Knoppix boot with no problems. (albeit slowly) This version, however, just gives me tons of cloop read errors. I downloaded from the torrent, and verified that the md5sum of the ISO matches the one included in the torrent (7ee0382655abf194aa300a98100cacde). It boots fine on my other two laptops. Any ideas? I will say that it took me two tries to get the torrent dl b/c of file corruption and md5 sums not matching.
[edit] Should say it was d/l'ed on my Gentoo laptop, and burned using xcdroast. I have burnt the ISO to two different cdr's to test. Both give the same read errors.
Have you already tried to download the offcial version ? (not coming from a torrent source).
http://www.knopper.net/knoppix-mirrors/
Sounds like you might need to clean your CD drive

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