12 Replies Latest reply: Jun 19, 2013 3:00 PM by The hatter
pullman Level 4 Level 4 (1,135 points)

I want to upgrade the internal drives of my 3,1 Mac Pro to Sata 3. My data is on two 3TB Seagate drives (Sata 3) and the boot volume is on a Mercury Extreme (Sata 2) SSD, which I will replace.

 

The MAXPower RAID mini-SAS 6G-1e1i PCIe card gives me Sata 3 on the data drives but is, apparently, not bootable.

 

How do I get an internal bootable Sata 3 connection?

 

I've seen the Mercury Accelsior PCIe card to which one could attach an mSATA SSD,such as the Crucial m4, but will that really result in Sata 3?

 

Would an external drive on an eSATA connection be bootable? Will it throttle a Sata 3 drive? I don't know much about PCIe (though I did read this Apple article which didn't clarify it for me).

 

Can one use the optical bay somehow?

 

Thanks a lot for any insight.

Philip


Mac Pro, Mac OS X (10.7.5), 2x3TB 1xSSD ACD 23 inch Epson R1900
  • 1. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    Grant Bennet-Alder Level 8 Level 8 (49,255 points)

    How do I get an internal bootable Sata 3 connection?

    Rotating drives available today, whatever their SATA spec, can source data off the spinning platters no faster than about 125MBytes/sec.

     

    SATA 3 is rated at 6G bits/sec, which theoretically is about 750 Mega Bytes/sec

     

    SATA 2 is rated at 3G bits/sec, which is theoretically about 375 Mega Bytes/sec

     

    SATA 1 is rated at 1.5G bits/sec, which is theoretically about 187.5 Meg Bytes/sec

     

    None of the SATA Busses is a bottleneck for consumer Rotating drives you can buy today. Trying to speed up the SATA Bus will not provide any real-world performance increases for Rotating Drives.

     

    Even most common SSD drives are not bottlenecked by SATA 2.

     

    -----

     

    If you put the drives on a PCIe card, they are not bottlenecked by the SATA on the card either, as it will typically be SATA 3.

     

    But unless you have the very fastest SATA drives available, you are in no danger of having the existing main SATA 2 Bus in your Mac Pro slow you down. The card is only needed for the fastest SSD drives available today, and will not provide much current speed improvement even in that case.

  • 2. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    The hatter Level 9 Level 9 (58,880 points)

    Why? you realize your internal drives are 125-140MB/sec and don't need the bus bandwidth.

     

    An SSD w/ SATA III like Samsung 840 will deliver a huge improvemernt.

     

    Putting SSDs on PCIe SSD cards like 6G Sonnet Tempo or others do give you more bandwidth and that leaves you your 4 SATA II slots and puts the SSDs on PCIe controller. I use it and works well. Some issues with 3,1 that isn't found though with later 4,1 and above.

     

    Only if you get a SAS/SATA III - and why would you? that connects into the iPass connector.

     

    Of course the optical drive bay is and has been popular.

  • 3. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    Grant Bennet-Alder Level 8 Level 8 (49,255 points)

    An SSD w/ SATA III like Samsung 840 will deliver a huge improvemernt.

    ... because that Samsung is a REALLY fast SSD. The speed of the SATA Bus just barely does not become a bottleneck.

     

    When Apple was making SSD decisions for the new Pre-announced Mac Pro, they decided to skip SATA altogether and put their newest fastest SSDs directly onto the PCIe Bus. It was such a good idea they carried it back to the new MacBook Airs. Anandtech benchmarked that at nearly 800G Bytes/sec ! (which would have been bottlenecked by SATA 3 if they had left it on the SATA 3 Bus).

  • 4. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    pullman Level 4 Level 4 (1,135 points)

    Thanks for the replies.

     

    The Seagate drives I have are rated at an average of 156MB/s, with about 200 max, but whatever the exact numbers I take your point that they won't saturate the Sata 2 connection. Thanks for clarifying that.

     

    About my wish to update the boot drive to a Sata 3 SSD, though, is there no way to get that performance using my MP's PCIe ports (or some other way, like with an external eSATA connection or such)?

  • 5. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    The hatter Level 9 Level 9 (58,880 points)

    Sonnet and OWC sell PCIe cards for SSDs, Sonnet you use your own which I like and they are $150 for basic unit to get you with one or two SSDs to boot from (or for data, or both).

     

    They boot and work best in 2009 and later.

  • 6. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    pullman Level 4 Level 4 (1,135 points)

    Thanks hatter. In the intervening time since my last post I discovered the two Sonnet Tempo cards. I have seen varying reports regarding the Mac Pro 2008.

     

    I'm still not entirely sure why the performance differs so much between the Pro and non-Pro cards. Any ideas?

  • 7. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    The hatter Level 9 Level 9 (58,880 points)

    do both have the same processor and cache on the card?

     

    one card supports 550MB probably and the other has two controllers and 900MB/sec. One is for RAID and the other low end supports boot drive and/or another but you don't need higher performance.

     

    I can't say it any better or different than Sonnet.

     

    Your 4x slots are not PCIe 2.0 though, they are 1.1 which will have some affect, unless you use, and it is supported in, the open 16x 2.0 slot.

  • 8. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    pullman Level 4 Level 4 (1,135 points)

    Yes I would have to install it in the 16x slot (which is currently unused). I could then use slot 3 or 4 for an esata card for an external enclosure with data and backup.

     

    The tech specs don't set out the difference. At Macrumors someone speculated the difference in performance is due to a different controller being used but I guess it could be two controllers as well.

     

    I asked whether storagereview.com will test these cards - could be interesting in light of their test of the OWC Accelsior - but they replied they don't follow Sonnet so won't. Too bad.

  • 9. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    The hatter Level 9 Level 9 (58,880 points)

    Two controllers is a different controller. Highpoint has done that with their 2-port and 4-port cards where you use one from each controller.

     

    Sonnet is very responsive to email.

     

    Barefeats has i THOUGHT looked at both OWC and Sonnet and compared the two brands.

  • 10. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    pullman Level 4 Level 4 (1,135 points)

    I've emailed Sonnet and, like you said, they were very responsive. Here's what they wrote:

    The difference between the two cards are:

    1) Tempo SSD is a modular, two part card and can fit into a smaller slot with one SSD mounted or a full length slot space with two SSDs mounted. The Pro card is a full length card.

     

    2) The Tempo SSD Pro has two controllers, one for each SSD and the Tempo SSD has one controller to share between two SSDs. When the two SSDs are configured in RAID 0, the Pro achieves the higher performance because of the dual controllers and a couple of other tricks. The performance delta is most significant with the card in a Mac Pro,  than with a Thunderbolt expansion chassis.

     

    I found the barefeats article. Interesting results, esp. when compared with the Accelsior. Rob notes that the Pro card uses a PLX PCIe Switch.

  • 11. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    pullman Level 4 Level 4 (1,135 points)

    Just to update with the latest info i received from Sonnet. I asked what the B serial number, mentioned on their site, means in terms of bootability. This is what Sonnet CS replied:

     

    "Initially our Tempo SSD cards were not bootable on a Mac Pro.  For the past couple months all currently shipping cards are serial #B cards and are bootable."

  • 12. Re: Turn Mac Pro 2008 (3,1) internal drives into Sata 3?
    The hatter Level 9 Level 9 (58,880 points)

    Great... surprised they left off the "bootable on 3,1 and later" - I thought that footnote was not made obvious enough on the OWC product page (they say they put what Sonnet has) and it is on Sonnet web site product in small print.

     

    I had bought it hoping it was bootable on ALL Mac Pro models (running Lion 10.7.5 or later).

     

    So now tell us how performance turns out.