Mikkel:
More information about your hardware would help. I know there is a problem with some SATA controllers that also the PATA controller for the optical drive.
No ATA involved here - only pure IDE. All of this hardware (all 3 computers) are vintage 1999 - 2004 (I don't know if that matters).
Is there anything else to mention about the hardware?
If that is not the problem, you may be able to use hdparm to turn on DMA. (It should have been turned on in the BIOS...)
Are you saying that my problem is more likely that DMA is *off* (and should be on)?