Should'nt have HDD's and Optical Drives on same IDE, But...

I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD drive,
will that force the DVD drive to run at the slower speed that the CD drive
runs at ?

"Dave" wrote in message
link.net...
I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD
drive,
will that force the DVD drive to run at the slower speed that the CD drive
runs at ?


No, also with high speed busses at this point, mixing HD and optical is
becoming moot.

"Dave" wrote in message
link.net...
I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD
drive, will that force the DVD drive to run at the slower speed that the
CD drive runs at ?

Two drives on the same cable will run at the same IDE speed. This isn't a
problem though, as hard drives and other drives are still struggling to
catch up to ATA66 interface speeds. In other words, "slowing down" the
interface speed is not a problem. -Dave

Dave wrote:
I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD drive,
will that force the DVD drive to run at the slower speed that the CD drive
runs at ?


If you have an ATA 100 device with an ATA 133 device on the same bus,
the bus will run at ATA 100 transfer rates for both drives.

The speed of the drives, eg whether they are 64x or 1x, matters not -
if they are both ATA 133, the bus will run at ATA 133 transfer rates for
both of them.

You can run a CD/DVD on the same cable as an HDD, if they are both in
DMA mode and both are the same ATA rating, without adversely affecting
the HDD.

The slower reading rate (which is determined by the 1x 64 x rating of
the drive) simply means that the CD/DVD grabs the bus for transfers less
often than an equivalent HDD would do. Thus a pair of hard disks is
better split between the two IDE cables - provided anything else on
those cables has the same ATA 100/ ATA 133 rating as the HDD and is
running in DMA mode.

However, if the CD/DVD is not in DMA mode then the processor has to poll
it for data, which will result in additional bus activity which will
impact on the performance of an HDD on the same cable. If the CD/DVD is
not in DMA mode, it should not be put on any cable with a HDD or
anything which can run in DMA mode.

Just about the worst thing you could do is to put an ATA 133 HDD on the
same cable as a non-DMA ATA 33 CDROM.....

--
HTH
Sue

DVD drives and CD drives transfer data in the same general realm of speeds,
which is MUCH less than current harddrives do. So the instructions you read
are correct.

--
DaveW

----------------
"Dave" wrote in message
link.net...
I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD
drive, will that force the DVD drive to run at the slower speed that the
CD drive runs at ?

Thanks ALL for your input.

"Dave" wrote in message
link.net...
I,ve read on a PC building site that one shouldn't put an optical drive
(such as CD or DVD) on the same IDE connection because that will force the
Hard drive to run at the slower speed of the Optical drive.

OK, but if there is a CD drive on the same IDE connection with a DVD
drive, will that force the DVD drive to run at the slower speed that the
CD drive runs at ?