non-ATA66 cable?

David Kelly dkelly at
Mon Oct 23 13:50:16 UTC 2006

On Mon, Oct 23, 2006 at 04:22:35PM +1300, Juha Saarinen wrote:
> >Assuming you have the right cable, make sure you have it connected
> >correctly.  I had a problem like this once, and it turned out that I
> >had put the cable on backwards.  I had connected the end of the cable
> >meant for the motherboard to the device (a disk, iirc), and visa-versa.
> >
> >I switched the cable around, and then it worked fine.  Of course, I
> >didn't discover this until after a few years, while I was in the
> >process of replacing that PC!
> !
> That made me go and check my machines here...

Mentioned earlier that the problem has been resolved as "operator
error". That my device is not capable of more than 33 MB/sec. That it
"only" writes at 8x which is roughly 11 MB/sec. The reason for my
investigation is that the drive spins at different rates (as measured by
ear) during a burn.

Probably ought to make sure DMA and all that good stuff is enabled as
well. IIRC DMA or something similar was disabled by default for optical
drives due to the number of broken devices claiming to support it.

As for the cable on backwards, its keyed with a tab on the outside
perimeter and inside with a blocked hole or two. Should be very hard to
install incorrectly. Back in the bad old days of floppy drives it was
common for a floppy to not have a shroud around the pins making it easy
to install the cable off by one or more. Also the "key" for the
connector was often a notch in the PCB, so it was easy to put the cable
on upside down.

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

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