Am I slowing down my ATA133 HD with my DVD-RW?

[jp1]

A new system I'm putting together has the following three IDE drives:

ATA133 HD - 40GB
ATA133 HD - 160GB
Plextor 716 DVD-RW


This computer will be used to record multi-track audio - and for that
reason, I'd like to have my second HD (the "recording drive") as the
only device on the Secondary IDE channel.


So, I've placed my smaller "system" HD on the Primary IDE channel with
the DVD-RW.
I'm using an 80-wire cable, with the HD set to Master and it is on the
end connector. The DVD-RW is set to Slave and it is on the middle
connector.


This is what I am seeing in Device Manager:


Primary IDE Channel
"Current Transfer Mode"


Device 0 - Ultra DMA Mode 6
Device 1 - Ultra DMA Mode 4


So, it appears to me that both drives are operating at their fastest
possible speed. BUT, I've always heard that placing a slower drive on
the same IDE channel will slow down the faster drive to the same speed.

Is this true? Is my HD really working in Mode 6 like it tells me? Or is

the DVD-RW really slowing it down to Mode 4 without reporting it?


Thanks in advance!


-JP

 

[peter]

One drive slowing the other on the same channel is a thing of the
past........
peter

 

[Jim Lewandowski]

Just so happens I added a new 200G HD to my system.

I had 1 HD (IDE 0) and 2 opticals (IDE 1).

I have since changed it to:

primary HD master IDE 0
DVD RW slave IDE 0
CD rom master IDE 1
old HD slave IDE 1

I even phoned Seagate's tech. support and they said "don't mix HD and optical". This is
likely not because they don't know but probably for liability use the
least-common-denominator scenario. They also said you "had to connect master to the black
connecter" when technically you don't if you have the master/slave jumpers on.

Well, after swapping in the new drive, the "Knight Rider" (I love the person who coined
that description) left to right blue light thing during WINDOWS startup went from 7 passes
to only 3 passes with the mixed HD/optical config. Proof that it IS a thing of the past.
The drives are both 7200 RPM but the new one has 4x the cache on it. That explains the
perf. difference.

JL

 

[jp1]

Proof that it IS a thing of the past.

Everything I am seeing also seems confirm it works, it's just that I
can't seem to find any documentation on the net that says "it works
this way". They all still just say "don't mix hard drives and optical
drives", just like Seagate told you.

 

[Jim Lewandowski]

Old myths take FOREVER to die (I'm in the large IBM mainframe world and it's the same
way).

Search for IDT/Indenpendent Device Timing on google. Been around for years.

JL

 

[aus]

Ideally you should have all devices on separate busses - PATA (Parallel
ATA) devices share the bus when 2 devices are on it so there will be
contention when data is needed to be transferred over it at the same time.

As optical devices are slower they can stall the bus to some extent -
they are a fair bit slower than hard disks.

Would you actually notice?, well probably not under most circumstances
but it would be apparent if you were say streaming video from the hard
disk and writing a DVD at the same time (yes, unlikely).

To get a separate channel for the DVD just get an add-in ATA card to
give you a couple of spare connectors. These are about $25 - $35.