Try using the "DMA" cheatcode. It might just be that your Plextor drive requires it and many newer versions of Knoppix have it disabled by default. Check my post history for more info if you need to. It's been discussed at length eslewhere..
Knoppix 4.02 won't boot from a Plextor PX-740A, at least on my Asus P5WD2-E Motherboard with ICH7R chipset. I plugged in an older Samsung CD-R, and that boots Knoppix just fine. I was under the mistaken impression that IDE was IDE, but obviously not...
Try using the "DMA" cheatcode. It might just be that your Plextor drive requires it and many newer versions of Knoppix have it disabled by default. Check my post history for more info if you need to. It's been discussed at length eslewhere..

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