non-ATA66 cable?

David Kelly dkelly at
Sun Oct 22 02:15:05 UTC 2006

Dell PowerEdge 400SC, 6.2-PRERELEASE (altho this is an old issue)

dmesg says:

acd0: DMA limited to UDMA33, controller found non-ATA66 cable
acd0: DVDR <LITE-ON DVDRW SOHW-1633S/BS0K> at ata1-master UDMA33
cd0: 33.000MB/s transfers

The controller is properly probed as, "atapci0: <Intel ICH5 UDMA100  

This DVD isn't writing discs as fast as other brands on other  
machines and OS's (such as MacOS X). Lite-On has a newer firmware  
that I have not tried. But first was checking for any sort of errors  
or irregularities and came across this mismatch.

Lite-On says "Supported transfer mode : PIO mode 4, DMA mode 2 and  
Ultra DMA mode 2", so is there something I should do to my FreeBSD to  
make this device happier?

David Kelly N4HHE, dkelly at
Whom computers would destroy, they must first drive mad.

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