How to arrange HD and Optical devices?

[jmichna]

Have an EPoX 8K3A+ mobo, rev 1.2, latest BIOS, with onboard Highpoint RAID, plus two IDE ATA-100 channels. OS = WinXP Pro.

I've got two 45gb drives in RAID-0 array, and currently have a DVD-ROM optical drive on IDE-0 as master, and CD-RW optical drive on IDE-1 as master. All cabling in system is 80 strand (ATA-66).

I'm adding an 80gb HD (sole function is backup -- using Ghost -- for my RAID-0 array... been real lucky so far... twin IBM 75GXP "Death Stars")

Situation:
DVD-ROM runs at (U)DMA-4, and CD-RW runs at (U)DMA-2. If I put the new 80gb HD as master on (either) IDE connector, and put both optical drives on a single IDE channel, will both optical devices be limited to UDMA-2?

Any reason to put/not put one of the optical devices as slave to the new HD?

A friend suggested that since the sole purpose of the new 80gb drive is as backup, to put that HD as slave to the faster of the two optical devices.

I know earlier mobos/IDE controllers would default to the lesser transfer mode, but what about the 8K3A+ mobo?
TIA,
jmichna

[Siliconjunkie]

As far as I know all IDE controllers will default to the speed of the slowest device in the chain. I would never put an optical drive on the same channel as a HDD unless there were no other options.

Put your optical drives on one, HDDs on the other.

[jmichna]

Got the following info from Repo Man at OAO Forums:

If you are using 80 strand cable for your optical drives, that is probably why it shows that way. I don't think it offers any performance benefit, but it doesn't hurt either.

I did some Googling.

Quote:
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# Independent Master/Slave Device Timing: Hard disk controllers on modern systems support running the master and slave device at different speeds, if one supports faster transfer modes than the other. Some systems, however, especially older ones, do not. If you are using two devices with radically different maximum transfer rates, and the chipset doesn't support independent timing, you will slow down the faster device to the speed of the slower one.

# Hard Disk and ATAPI Device Channel Sharing: There are several reasons why optical drives (or other ATAPI devices) should not be shared on the same channel as a fast hard disk. ATAPI allows the use of the same physical channels as IDE/ATA, but it is not the same protocol; ATAPI uses a much more complicated command structure. Opticals are also generally much slower devices than hard disks, so they can slow a hard disk down when sharing a channel. Finally, some ATAPI devices cannot deal with DMA bus mastering drivers, and will cause a problem if you try to enable bus mastering for a hard disk on a channel they are using.

Since the transfer modes associated with the IDE/ATA interface are constantly being improved, new devices support faster transfer modes than older ones do. In addition, hard disks often support faster transfer modes than ATAPI devices such as optical drives do. Yet, these devices can be combined on the same IDE/ATA channel, raising the question of compatibility when the devices are together.

The ability of an IDE/ATA channel to operate a master and slave device using different transfer modes is called independent device timing. The hard disk controllers integrated on modern chipsets all pretty much support independent timing, as do modern add-in controllers, but this was not always the case. Independent timing can be an issue if, for example, you upgrade an older PC and get a new, high-speed drive, but want to continue to be able to use the older one on the same channel with the new one.

If your system does not support independent device timing, and you use a newer hard disk that supports PIO mode 4 on the same channel as an older hard disk that operates only at PIO mode 0, the system will knock down the PIO mode to 0 for both drives. This will hamper the performance of the newer hard disk. The lack of independent device timing on many older systems is one reason why placing ATAPI devices like CD-ROMs on the same channel as a fast hard disk is usually not recommended. (It should be pointed out that we are talking here about the interface or external transfer speed of these devices. Reducing the speed of the interface only causes big issues if the effective interface speed becomes less than the sustained transfer rate of the disk. For a full discussion of these issues, please see this page.)

Again, today's chipsets all pretty much support independent timing, so this is less of an issue than it once was. However, there are still other good reasons to be careful about how you assign drives to the IDE/ATA channels in your system; see this page for a full discussion of these issues.
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http://www.pcguide.com/ref/hdd/if/ide/conf.htm

I think it is because older motherboards did not support independent device timing that people still say that your system will slow to the slowest drive on an IDE channel. But reading through that article still supports not having optical drives on the same IDE cable as your hardisks.

[stroyal]

why not add a 1 or 2 channel PCI controler to seperate things.
I do it so I can rip and load programs from cd to hd at max speed.

[jmichna]

Originally posted by stroyal
why not add a 1 or 2 channel PCI controler to seperate things.
I do it so I can rip and load programs from cd to hd at max speed.

I supose that's another option, but right now I've got a total of 4 channels -- 2 slave spots open on my RAID controller, and 2 slave spots open on my IDE-0 and IDE-1 channels... all I want to do it add that new HD -- somewhere -- as a backup storage device for my RAID-0 array, yet not hurt performance of the quicker of the two optical drives. I can't add the new drive as a (non-RAID) slave to the RAID controller, and I'd rather not add another IDE controller.

I am not at all likely to burn data from that backup HD to the DVD burner; DVD-ROM-to-DVD-Burner, or RAID-to-DVD-Burner are the more likely uses.

That "DVD-ROM-to-DVD-Burner" use leads me toward connecting the new HD as the slave on the same cable as the faster of the two optical drives.

[stroyal]

If the optical drive is not running when you are doing backup or restore with the new drive does performance get degraded.
this has never been clear to me.

[jmichna]

Originally posted by stroyal
If the optical drive is not running when you are doing backup or restore with the new drive does performance get degraded.
this has never been clear to me.

The excerpts of articles provided by Repo Man (see above) say that -- provided your chipset/mobo supports "independent device timing" - the speeds of the two devices on that channel remain independent of one another, so the hard drive's performance would not be degraded.

In my case, my mobo, the optical drives, and the HD are all newer technology components, so I wouldn't expect any issues.

[keithpb]

Originally posted by stroyal
why not add a 1 or 2 channel PCI controler to seperate things.
I do it so I can rip and load programs from cd to hd at max speed.

Things to remember: 1. Two Optical drives on one IDE port should work fine. However--WARNING-WARNING.... MS XP Pro. is easily confused. It's best to disconnect or remove ALL ancilliary storage ports except the HDD ON IDE 0, DRIVE 0, and ONE CD Rom on IDE 1, DRIVE 0. ALL OTHER IDE, SCSI, USB, & 1394 storage device/ports should be DISCONNECTED. 2. IDE will only write to ONE device at a time. 3. Some drives don't like each other, so if one master/slave configuration doesn't work, reverse it. Apparently, Microsoft thinks Windows XP should program its users. So, how do you know if you've been XP programmed? That's simple, a user's programming is complete when XP starts working for him instead of against him.

[jmichna]

keithpb...
What are you trying to convey with the above quote?

BTW, welcome to TechIMO.

[keithpb]

Simple...

Microsoft spent so much effort makeing XP think for the user, they forgot to let the user think for himself,

Does anyone know why Microsoft makes XP Pro start up like XP Home? Shouldn't a PROFESSIONAL product be designed for professionals? Why does the XP Pro help, assume I'm a 12 year old kid, and require Microsoft Messenger to work? I don't want messenger. I'm capable of finding answers without knocking on Microsoft's door. While I'm asking, why does Microsoft, when installing patches, INSIST on starting services I DISABLED??? Correct me if I'm wrong, but isn't it my computer, or did Microsoft, by reason of my installing XP, assume full control and ownership? Now, I suppose, the MS Zone's in full controll?

I want a PROFESSIONAL OS - NOT A CUTSIE GAME AND MUSIC MACHINE. I don't like my resources gobbled up by a dozen services I don't need, won't use, and DID NOT ASK FOR — yet, Microsoft, in their arrogance, installs XP PRO in the most unprofessional manner possible.

Think about XP's default install ...
* Open explorer and you get icons, but their captions are truncated to uselessness because long file names won't fit in the WINDOWS 3.0's caption space. How many icons are named: "Shortcut to no...."?
* File extensions are automatically HIDDEN. That does everyone a big favor. Now viruses are passed with names like "nicole.jpg.exe" so the unwarry, only seeing "nicole.jpg" opens the ".exe" and is welcomed to a nightmare.
* Microsoft insists on using spaces in its current directory naming structure, yet for backward compatibility, often can't decipher it.
* Halfway through an installation, XP reassigns drive designations, then isn't smart enough to look for itself among the list of CD type drives. Nope - like a dope, it just keeps asking you to put the CD in the X: drive, even though its location hasn't changed.

Believe it or not... after beating the MS out of it, I kinda like XP.