2 HDDs, CD, and CDRW 3

[nelljack]

On my new system I have the above list. The setup now is one Hdd and a CD drive, then the 2nd HDD and the CDRW. Is this the way to set the computer up for speed? I always was told if you put a slower device on with a HDD the speed slows down to the slower device (CD or CDRW).

Any input will help me decide if I should switch them around.

 

[xexth]

I never set up my computers this way. I always put the harddrives on one cable and the cdrw and the cdrom on the other cable (secondary ide). I also put the CDRW as the master and the cdrom as the slave. Works better that way (also recommended by some manufacturers). From what I understand putting a cdrom on the same cable as a fast harddrive does slow the drive down -
I hope this helps you.
Best Wishes
Xexth

 

[CitrixEngineer]

There was a lengthy discussion on this recently - check it out for intricate detail ;-)

It is also my understanding that putting an ATAPI device (CD-Rom, DVD-Rom or variants) on the same cable as hard disks will slow the hard disks down.

The ultimate solution is to have each drive on its own IDE channel. This is possible by utilising on-board RAID controllers as extra IDE channels, or purchasing an add-on card. However, these controllers can be problemmatic, IME.

I hope this helps CitrixEngineer@yahoo.co.uk

 

[nelljack]

Thank you both. This is what I thought. Now I can switch them the way it should be.

No more input should be necessary.

 

[cdogg]

I agree with Citrix. Since you have 4 IDE devices in your system, the best solution for speed would be to invest in an IDE RAID Controller. I have only heard good things about the Promise ATA/100 RAID controllers. An OEM version should only run you around $20-25. Check out

http://www.pricewatch.com

for the best prices.

If you decide to stick with your current configuration, follow xexth's advice. Keep the hard drives separated from the CDROM drives. This is because of 2 factors. #1 reason: many cdroms tend to use a protocol mode called PIO.

PIO is an older protocol that existed before DMA or ATA came about. PIO devices have to go through the CPU before they can access memory (RAM). Not only is the path longer, but it uses up your CPU in the process. DMA devices on the other hand have a direct link to RAM and aren't forced to go through the CPU first (hence, Direct Memory Access).

Hard drives need DMA due to their much higher transfer rates, while CDROM devices typically don't. Unless your positive yours is using DMA, then you'll want to avoid using the same IDE channel. All devices on the IDE channel will use the lowest common denominator - in this case PIO.

Hope that helps...X-)
~cdogg

 

[ANFPS26]

If my CD-ROM has DMA checked, then it should work okay as Primary Slave to the Primary Master Hard Drive, am I reading this correctly. I understand it doesn't work well as a PIO device, but if it works as a DMA device it shouldn't slow the HD down much, if at all, is that right?
Next question, if I wanted to put this CD-ROM as Primary Slave just to test and see how it affects my PC, where does one get a cable that would connect a CD-ROM and Hard Drive together. All the cables I have looked at are too short between the Primary and Secondary to reach a CD-ROM drive.???????????? "A little knowledge is a dangerous thing....."

 

[cdogg]

nobrain,

That's true. However, you must still be careful. Newer hard drives and mobos will allow the hard drive to operate at ATA/100 or ATA/133. As far as I'm aware, the newest CDROM drives only use ATA/66, though most still use ATA/33.

So, unless you can verify this at the vendor's website, you still risk slowing down the hard drive. Just because DMA is checked doesn't mean that you're using the fastest ATA protocol between the devices.

DMA can look like this:
UDMA-33 -> ATA/33
UDMA-66 -> ATA/66
UDMA-100 -> ATA/100
etc...

Hope that helps!
~cdogg

 

[ANFPS26]

Yes, but I'm still baffled about the IDE cable.......... "A little knowledge is a dangerous thing....."

 

[ectimo]

if u email me your home address, i could possibly send you an longer (and older) IDE cable.
The cables that i have are older cables pulled out of some old hypertower servers (about 3' in length, yes 3 feet)... so they will work for testing, but your speed might go down because of the cable age and they are 40 prong cables, not 80...(ata 33 not 66 or up)

 

[cdogg]

nobrain,

I just came across an article that stated that 80pin conductor IDE cables are restricted to 40cm in length. ATA/33 and PIO-Modes are the only standards that will work with lengths that are greater than 40cm.

Sorry to break the news. Do you have a full-tower or a mid-tower case? Consider going with a mid to avoid needing long cables.


~cdogg

 

[ANFPS26]

ectimo,
Thanks for the offer but I think I may try something with a Promise card. Still thinking........ "A little knowledge is a dangerous thing....."

 

[ANFPS26]

Thanks, cdogg,
I have a mid case, but I think I'm going to put all on seperate controllers with a Promise card and see what that does for me. "A little knowledge is a dangerous thing....."