Hi guys,

Just bought a Lite-on LTR-40125s and wondering how I should attach my drives. Read somewhere that if U attach both an ATA100 and an ATA33 device on the same cable, the ATA100 will downgrade to ATA33 speed.

I have 2X20gb ATA100 hdd, 1 ASUS 52X cd-rom and 1 Lite-On LTR-40125S. Whats the best way to connect all of this?

Thanks.

I personally would put each hard drive on Master for Primary and Secondary secondary channels, boot hdd on primary. Then put the CD-ROM on the channel that has the drive that you WILL be copying images to. Whatever is left is for the Burner.

With this setup you will have no problems coping on the fly or from your HDD.

The master and slave on an IDE channel can run at different UDMA speeds. So the Lite-on can run at ATA33 while the HDD can run at ATA100.

Weshy.

I have a different approach..but the HDD are IDE 1 as master and slave..the cdrom and cdrw on the secondary channel..this will give best HDD performance but on the fly copying will not be good..though you can do it...

Guess it depends on how important on the fly burns are...for me little..but I do have a extra IDE controller

There is no right answer to this question except, "try it". You may see no difference at all between the different configurations, or you may. It is entirely dependant on your hardware. I can do 48x CD copies On-The Fly with both drives on the secondary channel.
It would be foolish to configure based on what you hear here, it only takes a few minutes to try it and see. Use CDSpeed to test the transfer rates on blank 40x media and you will get your answer.
It's also good to note that putting a ATA100 HD on the same channel with a CD will NOT cause it to run at ATA33 if your system is ATA100 compliant, but again, try it and see. You will find it difficult, if not impossible, to cable the HD and CD drive together with the stock cables.

rdgrimes is right as far as an ata33 CD (atapi device) not bottlenecking a hard drive, because they are both using entirely different protocols altogether.

However, no matter what channels you put your HD's on, if you have one ata66 hd and one ata100 hd, they will both have to run at ata66. The drives are constantly talking to eachother, even when you're not doing anything, and it's impossible for the ata66 drive to talk as fast as the ata100, so the ata100 must slow down and talk to the ata66 in ata66.

CDROM drives and HD drives have no apparent effect on eachother, like I said the two different protocols operate seperately.

Also...a few facts to remember....ATAxxx is not running as fast as its rated at.

ATA133 normally transfers around 100MB/sec
ATA100 normally transfers around 70-80MB/sec
ATA66 normally transfer around 45-50MB/sec

My understanding is attaching a cdrom to same cable as HDD will degrade the HDD performance..are you saying this is untrue...then why is this always recommended ....

Please give a bit more info to help me understand this

Attaching a cdrom to your hard drive will not degrade the performance of the HD to that of your cdrom.

A cdrom uses ATAPI. A HD does not. They do not effect eachother.

I don't believe this has been recommended, you have just misread what you thought was recommended.

I believe what you read was that having a slower HD with a faster HD will degrade performance. That is true. Also what you could of read is that for optimal transfer rates you want to put the cdrom on another channel different from the HD, this is somewhat true, it depends on your unique configuration. Try it for yourself and see, we cannot tell you what your computer is going to behave like.