Will CD-RW slow down HDD UDMA100 if they are on same2nd IDE

[jkmin]

Please forgive me asking this question again.

I searched this forum and found out that some people say slower device will reduce the HD speed if they are put on the same IDE controller,and some say due to technology changes, it will not.

Will CD-RW slow down HDD UDMA100 if they are on same 2ndary IDE controller?

I have 40GB HD UDMA100 on the primary IDE, and CD-RW and DVD-ROM on the 2ndary IDE. Now I am adding one dedicated 80GB HD UDMA100 for the video capturing away from the exising C drive on the primary IDE controller. If I mix the new HD with CD-RW or DVD-ROM, will the new HD data tansfer speed slow down due to the slower device on the same IDE controller?

Thank you very much for help.

[mh2360]

Ok both CD ROMs on secondary and one HD on Primary? yes?. Simply slave the new HD to the existing one on primary....

[xzarkad]

Just one question:

why don't you add the second hardrive to the first IDE controller?
Do you have RAID? (if not, then you can only attach two devices to one IDE controller)

Normally the logic was like this:

if two different devices were attached to one IDE controller, the slowest would define the speed of the IDE controller. If the slowest device was working with PIO mode 4, and the fastest with DMA, then PIO mode 4 would be use for both devices. Nowadays this rule is not applicable anymore. I think that this depends on your mainboard, chipset and OS.

[mh2360]

Putting a HD on the same channel as a CD drive might cause speed problems, but you would have two HDs on the same channel, so no problems

[jkmin]

Normally the logic was like this:

if two different devices were attached to one IDE controller, the slowest would define the speed of the IDE controller. If the slowest device was working with PIO mode 4, and the fastest with DMA, then PIO mode 4 would be use for both devices. Nowadays this rule is not applicable anymore. I think that this depends on your mainboard, chipset and OS.

Thank you for the reply. I have Dell Dimension 4100 with Intel PIII 933Mhz, 256MB memory. I do not know the Motherboard and chipset name for this model. So do you think it is ok to mix CD-RW drive with HDD UDMA100?

I do not have raid. The reason I am putting the 2nd HDD on the 2nd IDE controller away from the C drive(on primary IDE controller) is that I read from some post on this forum, indicating that the C drive can be accessed by the OS while video-capturing, and it can cause the frame dropping if the two HDD's are put on the same primary controller.

[jkmin]

Putting a HD on the same channel as a CD drive might cause speed problems, but you would have two HDs on the same channel, so no problems

Thank you for the comments. Please see my reply above to see if it makes sense. Thank you.

[mh2360]

Normally the logic was like this:

if two different devices were attached to one IDE controller, the slowest would define the speed of the IDE controller. If the slowest device was working with PIO mode 4, and the fastest with DMA, then PIO mode 4 would be use for both devices. Nowadays this rule is not applicable anymore. I think that this depends on your mainboard, chipset and OS.

Thank you for the reply. I have Dell Dimension 4100 with Intel PIII 933Mhz, 256MB memory. I do not know the Motherboard and chipset name for this model. So do you think it is ok to mix CD-RW drive with HDD UDMA100?

I do not have raid. The reason I am putting the 2nd HDD on the 2nd IDE controller away from the C drive(on primary IDE controller) is that I read from some post on this forum, indicating that the C drive can be accessed by the OS while video-capturing, and it can cause the frame dropping if the two HDD's are put on the same primary controller.

But putting it on the same channel as a CD drive would be worse i would think....

[xzarkad]

Two harddrives on the same IDE channel can cause framedrops in theory, but this hardly happens. This also depends on your motherboard and chipset.
I suppose that your mainboard supports at least UDMA 33, or maybe 66. In that case, it should not be a problem.

I think that your system still follows the "old" logic. This means that the CD drive will slow down your harddisk, and this will cause framedrops. You could check in which modes your CD and / or DVD drive communicates with you mainboard: if this is PIO mode 4 or faster, then maybe it will not slow you down too much for capturing. Pio mode 4 has a theoretical transferate of 16Mb per second. DMA on the other hand follows the rules of the combination of mainboard, chipset and hardrive, which is probably UDMA 33 (MB per second)or 66 (MB per second)

But please note this: some mainboards automatically slow down the second device in the second IDE controller to PIO mode 2. If this is the case, then your second hardrive will automatically slow down to PIO mode 2, and this is much to slow for capturing.

I hope this helps a bit.

[boty50]

Hello,

to get best solution, as i did, buy inexpinseve new PCI/IDE
card, some support 100, and newer support 133, connect your
CD-RW to it, and here you are, having independent channels
for every device + extra ide interface for another device,
as these cards has 2 ide connectors.
you can find it here
http://www.linden-computech.com/index3.htm

[jonhildrum]

With the newer motherboards - last few years - it effectively makes no difference how you connect the various drives to the IDE interfaces. Each drive is handled independent of the other even on the same channel.

Thus, it is not uncommon to use two hard drives as masters on the primary and secondary controller - connect a CDRW as a slave on the first and either a DVD drive or a zip drive as slave on the second.

The only item one need to be careful with is when using some of the raid capable controllers added onto motherboards as 3 and 4 ide interface. Some of these chips does not like ATAPI type devices and it is normally preferrable to only connect hard drives to these.

[jkmin]

Jonhildrum, I think you are right.
I connected PM-HD, PS-DVD-ROM SM-HD, SS-CDRW, and I used a benchmarking software to measure the speed of the 2 hard disk.

They are almost the same or better on the SM-HD, which does not have OS on it. OS is on PM-HD, which is C.

I think there are lots of misunderstanding and misknowledge on combining HD and slower IDE devices such as CD-ROM on the same conntroler like SM(2nd master) and SS(2nd slave)

Thank you for the reply.

[Hong Kong Phooey]

Plug your 2nd Hard disk into the Primary IDE connection & make it a slave to your system Hard disk.
The major things to avoid framedrops on the new drive will be to keep it free of directories & keep it regularly defragmented.
Other factors to affect speeds are the speeds of the drive, ie: is it a 5400rpm ATA/UDMA 100 drive or a 7200rpm?
I have a separate 7200/ATA 100 drive on the primary IDE connector & I don't experience any frame drop issues now.
Remember, frame drops can also occur due to bad footage, but for example say 8 dropped frames out of 34000 is virtually unnoticeable.

And whatever you do, keep the CD drives on the other connector. As has been mentioned before the speed will default down to the slowest device.