IDE cable?

Garrett Cooper youshi10 at
Sun Jul 29 20:45:48 UTC 2007

illoai at wrote:
> On 29/07/07, Gaye Abdoulaye Walsimou <walsimou at> wrote:
>> Soo-Hyun Choi a écrit :
>>> Hi,
>>> This might be out of the scope in this list. But, would someone be able to
>>> tell me if an IDE cable for HDD and for CD-ROM is identical or not?
>>> Thanks,
>> The same yes
> With the aside that on some older machines the
> cdrom cable is 40 conductor which if used with
> a faster hard drive will prevent it from running
> above UDMA33 (I believe).  But it will work.

    Yes, that's true because pin-80 is twisted data/ground pairs which 
reduce crosstalk on the wires, thus allow the wiring to push UDMA133 
(133MHz), a value 4 times higher than the 40-pin max value.
    CD-ROM drives generally don't go above 66MHz though from my experience.
    You can determine if the cables are equivalent by noting the wire 
width (easy because the wire widths are about double), or wire count 
(there will be 40-pin or 80-pin). The number of pins on the PATA 
interface isn't different though, so comparing that way won't change things.
    If you're concerned about speed and/or signal quality, you may want 
to make sure that the cable isn't kinked at all. That will result in 
either slowdowns or failures due to data corruption.

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