At 05:50 AM 08/26/2000 , Jun Qian wrote:
>Someone else can give you more detailed info, but for myself, I will not mix
>fast and slow devices on same cable, I still believe that slow device (eg
>CDROM) will slow fast device down if they are on same IDE channel.
>
>Jun Qian
>----- Original Message -----
>From: <[log in to unmask]>
> > Hi group
> > I have question about the primary and secondary controller.  I have two HD
>(C
> > and D),
> > and I have CD-ROM (E), and CR-R/CR-RW (F).  The HD are on the primary
> > controller as master & slave.  the CD-ROM and CD-R/CD-RW are on the
>secondary
> > controller as master & slave.  Since a controller can only read or write
>at
> > one time,  can I put my second HD on secondary controller as master and my
> > CD-ROM on primary controller as slave?  If so, will copying from HD to HD
>go
> > faster?  will copying from CD-ROM to CD-R/CD-RW work faster?


Mr. Qian is correct based on a Bios written prior to January 1998.  These early
BIOSs could not deal with the translation of devices of differing speeds, such
as different PIO modes or UDMA speeds.  It would slow a faster device to
the speed of the slowest device on an IDE ribbon cable.   I have read reports
that some people are experiencing this again with the UDMA66 and UDMA100
controllers with a UDMA66 or 100 device and a slower IDE/ATA device on
the ribbon cable.

However, for the most part and it is my experience, that newer motherboards
or addon controller cards produced in the last two years have overcome this
problem.   In other words, you can added IDE/ATA devices in any combination
on a ribbon cable with no discernable decrease in device speed.  Personally,
I also continue to follow the old rule of keeping fast devices on the same
ribbon cable, if possible, just in case.

If it were me...  I would keep your ATAPI/CD Rom devices on the same
ribbon cable just for better compatibility.  It is not a requirement any more,
but I tend to be cautious.  I prefer stability over all else with a PC.

      Bob Wright
The NOSPIN Group

               The NOSPIN Group Promotions is now offering
      special "Free-After-Rebate" Software specials in conjunction
          with Beyond.com.   We have new offers all the time!!!
                      http://nospin.com/promotions