Tom Walker wrote in a message to Roy J. Tellason:

->  JH> They only have the std 40 pin configuration on the connectors. 
->  JH> AFAIK the extra 40 are most likely redundant grounds.

-> To give the cable better signal characteristics,  I guess.

TW>  Reduce Cross YTalk is the Official Term .Parallel wires tend to
TW> induce corrents i neach other. IF you check the IDe specifications
TW> there is also Length Limitations that normaly should not be
TW> cexceeded for HD cables..

Yeah,  I remember having to get longer cables once I started using tower
cases.    Particularly with VLB,  those slots were typically on
the side of the MB that would end up on the bottom of the case,  so I
needed more length to reach those plug-in cards.  Nowadays I'm just using
stuff built on to MBs,  which more often than not is much closer to the
drive bays...

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