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Serial ATA CD-Rom Drives?

OutRigged asks: "With Serial ATA hard drives starting to go mainstream, and being almost equal in price to their parallel equivalents, one would think we'd have Serial ATA CD-ROM drives by now. Yet wherever I look, all I see are PATA based CD-ROM drives. It's obvious that an optical drive will benefit little, if at all from using SATA, but why not switch for the sake of the cable size? CD-ROM drives are usually at the top of the case, and with the 1m limit in length, along with the small size of the cables, I see no reason not to use a Serial ATA interface in a CD-ROM drive."

16 of 70 comments (clear)

  1. or... by Blob+Pet · · Score: 3, Insightful

    buy a converter

    --
    "...today consumers have been conditioned to think of beer when they see a bullfrog..."
  2. Your answer. by lafiel · · Score: 3, Insightful

    Is pretty simple... extra cost.

  3. Why Not, good point. by haplo21112 · · Score: 3, Insightful

    I honestly had not thought that far yet, but you are right. If one were to build a machine entirely built on SATA tech, there would be a problem of where do you connect the CD-ROM/R/RW, DVD/R/RW...or even IDE Zip drive for that matter.
    It is probably getting hear time for these devices to start coming equiped with SATA connections. Which rasies and interesting question what if anything keeps them from coming with both connectors so they could be used with either IDE bus type. Other than price of putting the extra connector on the drive (and perhaps if needed embeding the converter from one connection type to another)

    --
    Power Corrupts,Absolute Power Corrupts Absolutely, leaving one person(group)in charge is absolutely corrupt.
  4. New case standard needed by Baron_Yam · · Score: 2, Interesting

    Damn, but I love it when you get a nice server, plug in those SCSI drives to a backplane mounted in the drive bay, and they all auto-address.

    It'd be nice if hot-swappable RAID5 IDE (complete with LED status lights) was worked out as a new standard for the home PC - one cable to the drive bay board, then plug in your drives without worrying about jumpers. It'd be even better if it used laptop-sized drives.

    I wonder if economy of scale would make that affordable if all the next generation of PCs were sold that way?

    1. Re:New case standard needed by UserChrisCanter4 · · Score: 2, Interesting

      Actually, I recall reading that they were considering shifting to 2.5" HDDs in the BTX standard. Note: This doesn't mean laptop Hard drives. Apparently, as rotational speeds have gotten higher, the size of the physical platters has shrunk in order to increase reliability (the force at the edge of the smaller platters is less at the same rotational speed). The 3.5" size simply exists now because it's a legacy standard, but they plan to phase down to 2.5" drives since it won't be an issue, space-wise.

      As long as the extra space isn't crucial for reliability (although I don't know how we could get LESS reliable IDE drives), I'm all for the smaller space requirements and the accompanying case designs they will afford.

  5. Cost margin by brejc8 · · Score: 3, Informative

    You can now get a cdrom for 10, cdrw for 20... The cost of developing a new product in order to sell it for 5 more is just not worth it.

  6. bridge chips by uberhund2 · · Score: 4, Interesting

    Most of the SATA hard drives are still just parallel ATA with a bridge chip to convert them to serial. I imagine that once manufacturers switch to native SATA hardware, the reduced costs will send SATA to CDs, DVDs, etc.

  7. IDE will never die... by Toxygen · · Score: 3, Interesting

    ...just ask your friendly neighbourhood floppy drive.

  8. Internal Firewire? by NanoGator · · Score: 2, Interesting

    Do they make internal firewire drives?

    I've never seen one, but I do have a card that'll do it. It has 4 ports going out the back, and one that's right on the card pointed towards the inside of the case.

    --
    "Derp de derp."
    1. Re:Internal Firewire? by Paladin128 · · Score: 2, Informative

      Though the raw bandwidth of FireWire is great, it has greater latency than SATA or PATA or SCSI. It's an external standard, and has support for things like multiple devices per channel and hotplug. This ads overhead to the data transmitted. Firewire is inherently superior to USB for storage, but not to the other internal standards. SCSI and SATA2 also support ordered command queueing, which ads to performance on multi-user systems.

      Plus, with drives today, SATA's "mere" 150MB/s will never be saturated.

      --
      Lex orandi, lex credendi.
    2. Re:Internal Firewire? by drinkypoo · · Score: 4, Insightful
      Like SATA, PATA, and (IIRC) unlike SCSI, 1394 can be installed as an asynchronous or synchronous bus. As such, it need have no more latency than anyone else. Programmatically it looks much like SCSI, being a register-based protocol. SCSI also has inherent support for things like multiple devices per channel and hotplug (All the mentioned standards support multiple devices per channel.) You can also do tagged queueing of firewire disks; they are typically attached via SCSI emulation. After all it's not the drive that supports ordered queueing, but the controller/host adapter.

      As for saying what with drives today SATA's 150MB/s will never be saturated, what about drives tomorrow? Why pick a standard without room for growth? Firewire is at 1.6Gbps today (though only in sampling quantities) and the 1394 WG has a plan to move to 3.2Gbps over fiber, providing 400MB/sec. As for "drives today", 800Mbps 1394 is adequate, with 100MB/sec transfer rates, since individual drives rarely provide more than 20MB/sec transfer under any conditions. However, 1.6Gbps 1394 provides more bandwidth than SATA, and allows you to connect enough drives to utilize it. What's more, it's designed for external use, so like SCSI it is irrelevant where you put your devices. It allows greater cable lengths than modern-day high-speed SCSI, however.

      It remains to be seen how the upcoming serial version of SCSI will perform, but it is safe to say that it will continue to be costly. 1394 is easy to implement, flexible, full-featured, and here today. The only thing preventing hard drive manufacturers from making 1394-native (or apparently native - some cheaper SCSI drives actually have a SCSI to IDE bridge built onto the controller board) hard drives today is the lack of demand. What I don't get is why there is a lack of demand; More and more PCs can now firewire boot, macs can firewire boot, and it would be lovely to diminish the number of goofy interfaces on the system board. Realistically, you need only USB2, IEEE1394, and an AGP slot to cover 99% of users. (Not counting the DIMM slots, CPU socket, etc, of course.) Input devices and network interfaces can go on USB2 (I would also like to see systems have onboard GigE, though), your video can go in an AGP8x slot, and storage devices can live on 1394. This would produce a truly legacy-free PC, without making it more expensive; in fact simplifying it to this degree would reduce the cost. Meanwhile, those who require legacy IO can plug something into USB.

      ATA is terrible. SATA is much better, but still has silly limitations, namely cable length (if it doesn't support external drives, it sucks) and the number of devices. SCSI is pretty decent but the cabling is complex and every piece of the system is overly expensive. Firewire can replace all three of them even if we don't have native firewire drives, but it would make much more sense if we DID have them. Cheaper, faster, cleaner, better. Legacy-free. In other words, all the things we've been asking for. Why is there such opposition to such an idea?

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    3. Re:Internal Firewire? by Paladin128 · · Score: 2, Interesting

      SATA has a lot of advantages... the cables can be made cheaply, the standard form-factors of drives are designed to slide in/out of a backplane (which no one has made yet) and it has room for growth. The next gen version will support 300MB/s and splitting a channel into 15 other channels. There's also talk of an external version of the standard. Plus, it's largely backward compatible with ATA.

      As for SAS (Serial attached SCSI), it has some nice features as well. First and foremost, it's backward compatible with SCSI and compatible with SATA. That means you can take an SATA drive and plug it into a SAS controller just fine. The inverse is not true; SAS drives won't work on SATA. This means if someone wants to make a common SAS backplane for a PC case, one can just slide in any SAS or SATA drive in any combination. Very cool, as far as I'm concerned.

      --
      Lex orandi, lex credendi.
    4. Re:Internal Firewire? by drinkypoo · · Score: 2, Interesting
      It'll be very cool if the SATA on SAS plan comes to fruition. However, the cheapness of SATA cables just isn't motivation, after all 1394 cables are four conductor. The only reason they're expensive now is that not too many companies are making them.

      How is next gen SATA supposed to handle splitting a channel up like that? With some kind of hub?

      There are external versions of SATA now, but I don't know any details. Obviously they're proprietary. Until drives are meant to be external, I'm still turned off of SATA. Of course, I don't use SCSI any more because it's too pricy (unless you want smaller drives, or want to deal with SCA adapters, or of course have an SCA backplane/enclosure) so I have ATA disks in my PC.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  9. Money, Money, Money by mhw25 · · Score: 3, Insightful
    CD-ROMS/RWs/DVD-ROMs are commodity parts right now, with speed grades mostly maxed out around 52x. And since that speed had been reached some time ago, they have been designed around the old interface. You don't want to invest a lot of money redesigining them for a really thin margin market of uncertain longevity.

    Hard disk drives costs more, and you can sell the SATA ones at a premium, and yet most implementations used a bridging chip - there aren't that many native SATA disk drives yet.

    DVD writes may have a greater case for going to SATA - but if you are designing one you may not want to alienate the majority of people who may buy one. The market for this is so unsaturated that a buyer is as likely to be an ungrading from CD writers as one one who is buying a new system - many of which still does not feature SATA as standard - especially those DELL-type manufacturer who wants to cut every single cent possible from the cost of their components.

    Basically to do a proper SATA switch you will have to split your market, or make yourself a niche player at this moment. And unlike Hard Disks, there are far more optical drive manufacturers around a very price sensitive market.

    Most manufacturers I think will just make it as it is, and let people who really want a ribbon cable free system to use a converter.

  10. Google, Dammit by gwynnebaer · · Score: 2, Informative

    http://www.neoseeker.com/news/story/2326/

  11. Re:F*** that! by jonadab · · Score: 2, Insightful

    > What about DVDs? I think I'm the last geek in the US without a DVD in his PC.

    No, I don't have one. Don't have any use for one. I do have a CD writer...

    If software ever starts coming on DVD instead of CD, maybe I'll have to
    get one, I'm not holding my breath. The CD is too standardized; it'll only
    be replaced by something that's a *lot* better (i.e., holds a *lot* more).
    In the early days of PCs, people would by incremental upgrades because
    everyone who had a computer was a geek and wanted to push the envelope.
    After the 1.4MB floppy, enough regular people had PCs that the next several
    improvements (2.8MB floppies, remember those? What about LS120 SuperDisks?)
    never caught on. The thing that will eventually replace the floppy, and
    we're only *starting* to see this happen now, is the writable CD. That's
    almost a 500-fold improvement in storage capacity.

    The CD-ROM today is at least as standardized as the 1.44MB floppy disk was in
    1996. I predict it won't be replaced, for most people, with anything less
    than a 500-fold improvement in storage capacity (i.e., 300 GB), probably
    twice that or more. Frankly, with networking getting to be the way it is,
    there's very little reason to want a larger read-only drive than 600GB;
    anything that large you just download anyway. Pretty much the only reason
    to want a DVD drive is if you want to watch movies, but most people who
    want to watch a lot of movies have a television screen they want to watch
    them on, so they get one of those hardware DVD players. For those of us
    who don't care that much about movies, or don't have to see them the very
    instant they come out, VHS is still totally viable -- and necessary, if you
    want to watch anything you or your friends or family tape, because nobody
    seems to be buying DVD-recording video cameras. They cost too much I guess.

    Now, read/write drives are another matter, but the writable DVD drives
    and blank media cost so much more... the CD writer is the sweet price
    point by a very wide margin still at this point.

    --
    Cut that out, or I will ship you to Norilsk in a box.