IDE Drive Order?

[Dave Hardenbrook]

I am planning to upgrade my self-built system to add two new IDE drives.
I currently have a DVD-ROM as the Primary Master and my hard drive is the
Secondary Master; and I want to add a zip drive and a CD-RW drive.

I have been perusing Scott Mueller's _Upgrading and Repairing PCs, 13th
ed._, and on page 805 he claims that you should never put a CD/DVD drive
on the same IDE channel as the hard drive "because it can slow down both
devices". And also he doesn't say so in so many words, but he does imply
that the hard drive should be the Primary Master, rather than a
CD-ROM or DVD-ROM.

So what would be the optimal ordering for my drives after upgrading?
Should it be like this:

Primary Master : Hard drive
Primary Slave : Zip drive
Secondary Master: DVD-ROM
Secondary Slave : CD-RW

Would this setup give optimal performance for transfering files between
the hard drive, zip drive, and CD-RW? Would performance of any of the
devices suffer? Would another scheme be better?

Please let me know... Thanks.

 

[Ron Reaugh]

I am planning to upgrade my self-built system to add two new IDE drives.
I currently have a DVD-ROM as the Primary Master and my hard drive is the
Secondary Master; and I want to add a zip drive and a CD-RW drive.

I have been perusing Scott Mueller's _Upgrading and Repairing PCs, 13th
ed._, and on page 805 he claims that you should never put a CD/DVD drive
on the same IDE channel as the hard drive "because it can slow down both
devices".

That's generally not true. Combine the gadget that is least frequently used
at the same time as the HD but still well behaved device on the cable with
the HD.

And also he doesn't say so in so many words, but he does imply
that the hard drive should be the Primary Master,
True!

rather than a
CD-ROM or DVD-ROM.

So what would be the optimal ordering for my drives after upgrading?
Should it be like this:

Primary Master : Hard drive
Primary Slave : Zip drive
Secondary Master: DVD-ROM
Secondary Slave : CD-RW

That's ok. Make sure busmastering(DMA) is enabled for all four devices.
Put the HD at the end of the cable with the Zip in the middle.

Would this setup give optimal performance for transfering files between
the hard drive, zip drive, and CD-RW? Would performance of any of the
devices suffer? Would another scheme be better?

Not in general but specific problems might suggest a different combination.

 

[Fabien LE LEZ]

Put the HD at the end of the cable with the Zip in the middle.

Why?

 

[Ron Reaugh]

Why?

Depending of the mode the HD uses and the age of the Zip, the Zip might not
terminate the cable properly for the higher HD transfer modes.

 

[Rod Speed]

I am planning to upgrade my self-built system to add two new IDE drives.
I currently have a DVD-ROM as the Primary Master and my hard drive is
the Secondary Master; and I want to add a zip drive and a CD-RW drive.

I have been perusing Scott Mueller's _Upgrading and Repairing
PCs, 13th ed._, and on page 805 he claims that you should
never put a CD/DVD drive on the same IDE channel as the
hard drive "because it can slow down both devices".

Thats completely obsolete 'advice' now.

The more practical reason for not doing that is just that
its usually more mechanically convenient to no do it, just
because there isnt always enough distance between the
two drive connectors, particularly if the cdrom drive is in
the 5" bay stack and the hard drive is in the 3.5" bay stack.

And also he doesn't say so in so many words, but he
does imply that the hard drive should be the Primary
Master, rather than a CD-ROM or DVD-ROM.

Yeah, thats generally best, but usually both
approaches work fine with modern bios.

So what would be the optimal ordering for my drives after upgrading?

There isnt one basically.

Should it be like this:

Primary Master : Hard drive
Primary Slave : Zip drive
Secondary Master: DVD-ROM
Secondary Slave : CD-RW

That config should work fine.

Would this setup give optimal performance for transfering
files between the hard drive, zip drive, and CD-RW?

There is no such animal. While ever the source and destination
are on the same ribbon cable, that will in theory reduce the
speed of the file transfer, but the reality is that all the other
drives apart from the hard drive are so much slower than
the hard drive that in practice the difference is theoretical.

Would performance of any of the devices suffer?

What you can see is a situation where a slow drive
can affect access to the hard drive while say the slow
drive is seeking the heads to where they should be.

But again, in practice thats a very theoretical problem in the real world.

Would another scheme be better?

Not really.

 

[DeepOne]

[snip]

Primary Master : Hard drive
Primary Slave : Zip drive
Secondary Master: DVD-ROM
Secondary Slave : CD-RW

That's ok. Make sure busmastering(DMA) is enabled for all four devices.

If it's a Zip-100, it doesn't support DMA. The Zip-250 (and I assume
the Zip-750) do support it though.

 

[Folkert Rienstra]

Depending of the mode the HD uses and the age of the Zip, the Zip
might not terminate the cable properly for the higher HD transfer modes.

Serial termination is not the same as parallel termination and therefor
doesn't need to be at the end of the cable.
There is no such end of cable termination requirement in the ATA spec
with 2 devices attached.

 

[Folkert Rienstra]

That's generally not true. Combine the gadget that is least frequently used
at the same time as the HD but still well behaved device on the cable with
the HD.


That's ok. Make sure busmastering(DMA) is enabled for all four devices.

Devices do not busmaster, the host adapter does.
Devices use the ATA DMA protocol.

Put the HD at the end of the cable with the Zip in the middle.


Not in general but specific problems might suggest a different combination.

Right, there is no cover all.