SSD in 2nd optical bay + 4 HDD?

Discussion in 'Mac Pro' started by Loa, May 17, 2009.

  1. Loa macrumors 65816

    Loa

    Joined:
    May 5, 2003
    Location:
    Québec
    #1
    Hello,

    Very simple question: will this (title) work?

    Or is there a "hard" 4 HD limit? (In other words: by putting a SSD in the 2nd optical bay, would the mac pro only recognize 3 of the 4 internal bays?)

    Thanks

    Loa
     
  2. Tweak3D macrumors regular

    Joined:
    Jul 17, 2007
    #2
    if you choose to have only one optical drive then you can have 5 HDD's.
     
  3. Loa thread starter macrumors 65816

    Loa

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  4. sboerup macrumors 6502

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    Mar 8, 2009
    #4
    You could theoretically use 2 HDs in the 2nd optical bay drive if they fit, like 2 SSD drives.
     
  5. ekwipt macrumors 6502a

    Joined:
    Jan 14, 2008
    #5
    Are the sata controllers 3mbps though, and is the spped the same from the 4 internal bays?

    2008
    2009
     
  6. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #6
    3rd party mounts exist that allow you to do just that. But it's also possible to DIY something much cheaper as well, especially if you have an old optical drive of some kind lying around. Take it apart, and use the metal case plates. :)
    Yes, the SATA ports operate at 3.0Gb/s ;), and is the same for all of them. (Backwards compatible as well, if you should install an older drive that only runs at 1.5Gb/s). :)
     
  7. remmy macrumors 6502a

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    Jul 1, 2007
    #7
    I did this in a 2008 mac pro when I had a spare IDE hard drive I was going to use. The only thing was that the cables were a bit short but in the end was okay.
     
  8. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #8
    For a single HDD in an optical bay, the easiest thing I can think of, is a simple 5.25" to 3.5" adapter bracket. Rather inexpensive as well on eBay. ;) One of those items that the "Free Shipping" listings are truly wonderful. :D

    I really do like SATA cables better than IDE/PATA. :D
     
  9. Loa thread starter macrumors 65816

    Loa

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    Location:
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    #9
    In fact, as suggested by diglloyd:

    "The new Mac Pro Nehalem offers especially simple installation: the lower optical bay is pre-wired, and one can literally install the X25-M in under two minutes, without any tools. Just plug in the drive, and because there are no moving parts it’s not even necessary to secure it—just let it dangle there in the optical bay." (http://macperformanceguide.com/Mac-LightingFast.html)

    :)
     
  10. nanofrog macrumors G4

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    May 6, 2008
    #10
    Of course, but some might want to secure it anyway. ;) If someone doesn't care about appearance, things like zip ties or double sided foam tape could even be used. :) Personally, I would, as I wouldn't want to knock the system about accidentally, and have such an expensive drive bang against anything. Solder joints can, and do break under physical stress. Lead free solder is more susceptible to this.
     
  11. Mac Husky macrumors regular

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    Bavaria, Germany
    #11
    Sorry to hook in this thread, but I am thinking about two different setups:

    a)
    SSD with OS X and applications (optical bay)
    3 drives in RAID0 (bay 1-3) [e.g. WD RE3]
    1 drive for fully Backup (bay 4)

    b)
    3 drives in RAID0 including Mac OS X and apps (bay 1-3)
    1 drive for fully Backup (bay 4)

    Of course another external backup will be done.

    Do you guys think, the SSD is worth the extra money using it for OS X and apps drive instead of putting them in the RAID0 drives?
    OS X and apps should be very fast even beeing included in the RAID0 (~250% avarage speed). Noticeable faster from the SSD?
    Pros and cons?!
     
  12. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #12
    c)
    4 drives in RAID 0, installed in the sleds. 5th drive for backup in the empty optical bay. ;)

    You'd get a nice improvement in throughput, and likely at a lower cost than adding in an SSD (depends on specific drive). Not the same speed for random access, but you might get a better balance. Particularly if you're going to be doing a lot of writes.

    Details on specific usage might help though. ;)
     
  13. gesundheit macrumors member

    Joined:
    Oct 28, 2004
    #13
    I have setup "a)", although I only used the outer 1/3 of each of my 3 1TB drives in the RAID 0. Is it worth it? We're all going to have different answers for that - it certainly seems a bit faster, so that's all that matters to some of us. ;)

    http://forums.macrumors.com/showthread.php?t=690819
     
  14. Loa thread starter macrumors 65816

    Loa

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    #14
    That's exactly what I'm aiming for (when I'll have enough money!).

    Skipping on the SSD would indeed save you some money and give you more speed (by having a 4 drive RAID0), but for me it's essential to have the OS and data separated.

    And after reading diglloyd on a SSD boot drive, I'm sold! (See my link in previous post)

    A 3-drive RAID0 will be plenty of speed for my needs anyway.

    Nisaea
     
  15. Mac Husky macrumors regular

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    #15
    :D Right. Do you think, that´s the best solution? Was thinking about the Intel SSD.
    Nikon Capture NX2, Photoshop, InDesign, Final Cut Express (in my mind).

    To use only the periphere partition of each drive would be one more option, of course.
    I would like to have a setup, that isn´t to complicated and mixed up.
     
  16. nanofrog macrumors G4

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    May 6, 2008
    #16
    It allows for both fast reads, and writes anyway. It also gives a greater capacity, and better $/GB as well.

    Then there's the use of enterprise drives as you're interested in. Better UBE's for sure. Rather handy with RAID, and should be a high priority if you make a living with the system.

    The Intel SSD's are nice, and make a great single drive solution. Rather pricey for a stripe though IMO. You can do just as well, or better using additional drives that are less expensive per.

    If cost is no object, then you could do an SSD for OS, or even a stripe, then use mechanical drives for a stripe set for data writes. But I presume there is a budget constraint. :p
    Sticking to a single stripe for everything would simplify setup. As you mention, you can always partition for better throughput. Use the outermost tracks for the OS for example. Or apps,... :)
     
  17. Mac Husky macrumors regular

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    #17
    Thanks nanofrog. Very helpful statements again.
    When I got you right, you would say:

    a) if money doesn´t matter
    - SSD (or even 2 in a RAIDO :D - note: I´m not planning that ;)) for OS and apps
    - 3 or even 4 drives RAID0 (prefering enterprise drives) for data
    - of course additional backup strategy

    a) if money does matter :rolleyes:
    - 4 drives RAID0 (prefering enterprise drives) for OS/apps and data
    - of course additional backup strategy

    Do you agree?

    Going for a OS/apps-SSD in the optical bay (maybe I wouldn´t mind paying for it - not sure yet :rolleyes:) would mean only 3 RE3s in RAIDO to me as I want an internal backup using bay 4. Due to that: outperformer might be the 4 drive RAID0 solution with optical bay backup drive -notwithstanding the lower costs also?!

    Do you agree?

    Having a RAID0 of 4 drives, there might be no really noticeable(!) difference in speed by doing more partitioning to "produce" e.g. special outermost OS-tracks due to an already very fast system?!

    Do you agree?

    For the backup (e.g. as mentioned abough in the optical bay) I won´t need an enterprise drive, I guess?! So I could go for another 1.5 TB WD drive. I could reduce the capacity of the 4 RE3 drives to 250GB or 500GB. Price is coming down and more capacity couldn´t be backupped internaly at all. Four of them should do best and can be backupped fully using a 1.5 TB backup drive?!

    Do you agree?
     
  18. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #18
    Yes. :D
    You can actually fit a pair of 3.5" HDD"s in the empty optical bay. Use the metal cover(s) off an old optical drive. Just a screwdriver and a drill is needed, and is rather easy to do. But the best part is, it's really cheap. :D

    On the outside, you can get a ready-made mount, but it's expensive. Or you could go with an external enclosure for a single drive for the backup. Not necessarily a bad idea, as it's separate from the rest of the system (separate PSU). You can lock it up as well, and it's portable. It's up to you. I'd just strip down the optical drive and go that route, as there's less clutter. You might want to get external drives later for additional/portable storage. After awhile, it all piles up. :p

    SSD's are nice, but running the OS off a stripe is also fast. As I indicated earlier, the SSD's advantage is Random Access. The average throughput of a stripe can exceed the SSD, as they can hit ~250MB/s max ATM. A 4 drive stripe could put you at 330MB/s or so on enterprise drives. Perhaps a little faster on consumer units, but given the lower Unrecoverable Bit Error, I won't use them.

    Ultimately, I prefer to have a single logical drive for each set. The reasoning is simplicity. If you have multiple partitions, you get multiple drive letters show up in the system. No problem. But here's the rub IMO. If one of the drives does fail, ALL of those logical drives (partitions) are affected. And in the case of a stripe, they're just GONE (data). Fix the drive, and rebuild all of them, preferably from clones. Not fun.

    There may be cases where it's relevant to do so however. The only way I truly know to find out, is by experimenting. It takes a lot of time, but you'll get a better idea of your actual usage, and hopefully learn quite a bit about the recovery process as well. Particularly how tedious it can get. :eek: ;)

    No, you don't have to use an enterprise drive for a single disk backup. :) Given the issues with the 1.5TB models from Seagate, I'm leary of it, despite the supposed fix. I'm strange that way. :p

    On the RE3's, the 320GB would be faster than the 500GB model, and has more capacity than the 250GB. It also works out fairly well on $/GB as well. For a backup drive, take a look at the WD Green series. Perhaps even the 2TB model, particularly if you stick with the 500GB model, as it would all fit. A little slower (5400rpm), but they seem to be both quiet and reliable. Also, the backup doesn't have to be the same capacity as the entire array, so long as it can hold what's being stored on it. You can use multiple drives if necessary, but it would probably mean going external with one. ;)
     
  19. Mac Husky macrumors regular

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    Mar 28, 2009
    Location:
    Bavaria, Germany
    #19
    Thanks a lot, nanofrog.

    No problems with heat?!
    Power supply for 2 drives? Extra SATA-card needed? Where to plug in the second drive?
    Will be a Mac ´09.

    I planned a second external backup also. Of course I could do the first backup outside the Mac as well using the SATA of the optical bay. Planning a WD My Book extern. I will think about that, when going with a SSD to have a 4 drive RAID0 option.

    I found a very good overview posted by Tesselator here concerning the speed of RAIDs. No really need for SSD so far, when going with 4 drives I would say ;)
    Logical drives for a better tidiness, but bad to worst case for failure on one of the RAID drives. OK.
    Right. Want to have the backup fixed on one single drive. Maybe a second backup using a NAS.



    Summing all up - and I hope you do agree :D:

    4x Western Digital RE3 320GB, SATA II (WD3202ABYS) or maybe 500GB at least
    1x Western Digital Caviar Black 1000GB, SATA II (WD1001FALS) or Western Digital Caviar Green 1500GB, 32MB Cache, SATA II (WD15EADS)
    (the WD Caviar green has 7200 rpm also, but - as you mentioned - it is kind of slower - but has options up to 2TB)

    That should do for the first attempt - won´t it?!
    All together less expensive than just one(!) Intel SSD 80GB :):eek:

    If I should feel like "must have a SSD" later on, I could switch the backup disk to the outside of the Mac and use the optical bay for the SSD with OS and apps.
    But fortunately I dont think, that I will really miss a SSD so far, when going with 4 drive RAID0 :rolleyes:

    Maybe seperated OS/apps on a SSD will have advantages in case of failure, too?
    So that I should think about that again?
     
  20. nanofrog macrumors G4

    Joined:
    May 6, 2008
    #20
    For 2 drives in the optical bay, the heat produced won't end up killing them. :p There's actually some open space above them for air flow. :)

    Power is really easy via a 4 pin Molex to (2) SATA Y spitter (scroll down a bit). Or combination of Molex Y and a pair of Molex to SATA cables would do the trick, but is a little on the messy side.

    As for a SATA port, you would need to either disconnect the optical drive in the upper bay, and relocate it externally. I'll presume you don't want to do this, so a PCIe SATA card would be needed. Take a look at Syba. They work with Mac, and are on the inexpensive side.
    You might also want to consider getting the drive you want, and an empty external enclosure. They can be found inexpensively, and eBay might be the best source for lowest cost. Prices have looked good in the past anyway. ;)

    Your idea of a first attempt looks good. :D Please note, that WD's Green Power drives don't have a fixed spindle speed, but is variable. They usually spin at 5400rpm, and can be considered approximate to a fixed 5400rpm drive. That's why the performance isn't quite what you'd get off a 7200rpm (or better). I located a test someone performed on the WD20EADS (2TB), and it's Average STR was 77.7 MB/s IIRC. Not bad, but no speed demon either. :p

    As for SSD as a separate OS/app disk, it would be nice, but the cost seems harder to justify. Having it on a separate disk than the array can give you a little more security (no matter mechanical or solid state), but I'm assuming this system will be primarily for personal use, and therefore the time required for a recovery, is doable. It also gives one less drive for the array, or costs an additional drive. The cost factor varying wildly, depending on drive choice. :D :p

    If you just want an SSD, go ahead. I would recommend trying the RAID first though, as you would likely be very satisfied with the performance. And the cash saved is nice too. :D
     
  21. Mac Husky macrumors regular

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    Location:
    Bavaria, Germany
    #21
    I admit I wanted :D But a 4 drive RAID0 is impressive as well.
    If the system would be much easier to rebuilt after a failure on one of the RAID0 drive using a SSD for OS and apps, I would spend the money for it.
    But as it isn´t really a big deal to rebuilt a 4 drive RAID0 system including OS and apps (having a reliable backup) I would go for the RAID0 only.

    Of course hoping it will not be a "first attempt" only, but a very powerfull and secure system at all.

    Hope you don´t mind asking you again, when I start setting all up in June. Thanks again.
     
  22. nanofrog macrumors G4

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    May 6, 2008
    #22
    Meh... Skip the SSD. :eek: :p

    :cool: No problem. You're welcome to PM me if you wish. :)
     
  23. Mac Husky macrumors regular

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    #23
    I will so far:)

    What I didn´t include in my thoughts right now is:
    a) power consumption of 4 always active drives :confused:
    b) the noise of 4 always running drives :confused:

    What about that :rolleyes:
    I would like to return to that in a couple of weeks.
     
  24. sboerup macrumors 6502

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    Mar 8, 2009
    #24
    I bought a 120GB Vertex. It stung at $350. I never regret it, and looking at purchasing another it's so fast. Boot time is under 19 seconds from the time I press the power button. Apps load instantly. It's so fast.
     
  25. nanofrog macrumors G4

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    May 6, 2008
    #25
    Mechanical drives don't consume that much power. The WD3202ABYS for example, only uses ~9W each. Startup is higher, and really should be planned for. (You won't have to worry for 4 drives, as the MP has a large enough PSU). Fortunately, good (proper) RAID cards will use a staggered spin up to help with this (usually ~0.7s between drives). You really don't want 24 HDD's all spinning up at once, as startup power is in the 36W or so range. That can fry a PSU. :eek: And they have a bad habit of taking part of the system with it, like logic boards, memory,... when this happens. :(

    I usually don't have noise issues. Check the specs and any reviews, as they hopefully did a noise test as well. :) In my experience, the WD's aren't noisy. Though I've a full tower aluminum case, and they're mounted in rubber O rings for isolation. (They really do help). ;)
    They're definitely fast, but I'm waiting for them to mature, as well as the costs come down/capacity to increase. This also includes the need for OS's to accommodate SSD's specific needs (optimization, such as TRIM). No support so far, and I don't know of any TRIM util for 64bit versions (only 32bit).

    I'm also concerned with the MLC/SLC memory chips' write cycle length. A dead cell at 10k/100k writes, is too low for writing lot's of data in a high use system. (I don't want to have to worry about this, and tend to look at things in a worst case scenario). Even with some additional capacity for wear leveling or any TRIM implementation, it still can't reach the equivalent UBE of a mechanical drive ATM. There's just no way it jumps from 1E5 (SLC) to 1E15 for enterprise drives. It's worse for MLC (1E4). FeRAM can (1E16), but isn't available yet. :(

    For a drive used primarily for reads, it doesn't matter, so I do think SSD is great for an OS/apps disk as a single drive performance solution. Assuming the person is willing to part with cash. :D

    For me, the $350+ is better spent elsewhere ATM. :)
     

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