Biggest disappointment with new iMac - Port config

Discussion in 'iMac' started by jclardy, Jul 17, 2017.

  1. jclardy macrumors 68040


    Oct 6, 2008
    I'm not sure if i'm not alone here, but the only thing I don't like about my new iMac is how few TB3 ports there are on the machine. My MacBook Pro has twice as many.

    My problem is I have a TB2 RAID array, a USB-C 4k monitor, the eGPU dev box, and the 4 port USB-C hub that comes with the eGPU box from Apple (Messing around with some VR dev.) With those I've already gone over the number of ports (And none of them have a daisy chain port.) What I can do is use the eGPU plugged into the 4k monitor, but I can't do that till High Sierra. Even still, that is all ports used up.

    I guess my real issue is that the last gen iMac had the same issue, but less amplified. With TB2/MDP you had either fast storage or displays. But with this new iMac you have fast storage, displays, eGPU's or any USB-C device (Which is only going to continue to grow over time.) This iMac would have been absolutely perfect if they had done 4 TB3 and just 2 USB-A ports.

    But I guess we have to wait for the redesign, or double the cost and buy an iMac Pro. Or maybe someone will release a TB3 dock with some extra Thunderbolt ports, I only really need the full bandwidth for the eGPU, the others would be fine on a shared line.
  2. xWhiplash macrumors 68000

    Oct 21, 2009
    I wonder, are there any Thunderbolt hubs that would handle the daisy chaining for you?
  3. Arctic Moose macrumors member

    Arctic Moose

    Jun 22, 2017
    Gothenburg, Sweden
    Agreed, this is my only complaint as well. Four TB3 ports seems a reasonable minimum for an iMac 5K class computer.
  4. Fishrrman macrumors G5


    Feb 20, 2009
    The MacBook Pro has four USB-c ports that happen to be thunderbolt-compatible. Not the other way around.

    OP is something of a "unique case".
    Most users need more -USB- ports than they do thunderbolt ports.

    We're not going to see more than two thunderbolt ports on the back of the iMac for some time yet to come...
  5. CWallace macrumors 603


    Aug 17, 2007
    Seattle, WA
    I think it will happen sooner rather than later as USB-C adoption becomes more prevalent.

    As to the 2017 model, I am guessing the main reason is it was easier to engineer and manufacture effectively the same chassis (just swapping two TB2 for two TB3/USB-C ports) and there may have been some influence from all the complaining about "DongleGate" as I imagine it's more common for desktop users to have USB-A connector devices so Apple wanted to maximize the number of USB-A ports until the industry switch to USB-C is more in place.

    All that being said, I too would have preferred more USB-C ports, as well.
  6. xWhiplash macrumors 68000

    Oct 21, 2009
    iMac Pro has 4 Thunderbolt 3 ports on it. It is also a limitation on available PCIe lanes on how many ports can be used.
  7. jclardy thread starter macrumors 68040


    Oct 6, 2008
    I don't think that is really true. If Apple thought people wanted USB-A they would have left at least one on the MBP, which is the computer for "most people."

    This decision was likely to not have to change the MB/casing much at all (And maybe save money by having a cheaper thunderbolt controller?)
  8. Fester1952 macrumors member


    Jul 22, 2012
    Adelaide, Australia
  9. propower macrumors 6502a

    Jul 23, 2010
    I agree strongly with the OP. Today there are painfully few TB3 devices - especially any with two TB3 ports. There are only one or two of any of the following storage devices - TB3 SSD case? TB3 PCIe SSD? TB3 SSD array? TB3 audio interface. What I wish was that there were two TB2 and two TB3 ports. TB2 has been the pro standard for Macs for 5+ years. Now they are gone from our boxes and replaced with a port that barely has any devices. I have two TB2 audio interfaces, two TB2 docks and a TB2 SSD array. None with two TB2 ports :-(
  10. Glockworkorange macrumors 65816


    Feb 10, 2015
    Chicago, Illinois
  11. Chancha macrumors 6502a

    Mar 19, 2014
    I don't have hard numbers, but there may be not enough PCI lanes spared from the chipset since some lanes are taken for the internal 5K display, and then some for various I/Os, and obviously also the 4 USB 3.0-A ports also. So even if Apple did give us more than 2 TB3 ports, we may have a similar case like the 13" touch bar MBP where not all of the ports can run at full bandwidth.

    It would have been much easier to manage if there were 3 x TB3, and then 3 x USB-A in my opinion. But I can make do with having just 2.
  12. ApfelKuchen macrumors 68030

    Aug 28, 2012
    Between the coasts
    I'm not sure why this is a disappointment. The 5K iMacs have always had a pair of Thunderbolt ports. Now, it's USB-C/TB3, rather than TB2. The iMac Pro will have 4 USB-C/TB3 ports and 4 USB-A ports.

    Meantime, the 2016 MBPs were the first Macs to have more than a pair of USB-C/TB3 ports. I know, how can you keep 'em down on the farm after they've seen Paree? (ok, the nMP has 6 TB2's...) However, when you subtract 1 USB-C port for power/charging, the MBP effectively has 3 ports compared to the iMac's 2. Not quite as bad.

    While some users will undoubtedly appreciate having more USB-C ports, it's likely premature to reduce the number of USB-A ports. iMacs (even the 27") serve a wide range of users. At the lower end of the spectrum, the user may have zero need for USB-C/TB3 and can easily require 3 or 4 USB-A ports.

    Maybe it's just me, but perhaps some of the disappointment should be aimed at the makers of TB/USB-C peripheral gear that lacks daisy chain ports?

    After hearing from so many professional users who insist that any iMac (including the upcoming iMac Pro), is not a professional machine (because it's not modular), we now hear from people who do consider the 5K iMac to be a professional machine in need of greater I/O capacity than the 21.5" iMacs. You can't please all of the people, all of the time. ;)
  13. jclardy thread starter macrumors 68040


    Oct 6, 2008
    That looks like it would be the ideal solution, letting me use mDP for the monitor and having two free TB ports. Unfortunately a bit pricey and not shipping yet though.

    For me it is just the fact that more and more devices are going to be using USB-C which means that you now have way more devices competing for the same 2 ports. With Thunderbolt 2, you had RAID arrays and mini-display port monitors, and maybe some high end audio/video gear. Most people will be fine with just two TB2 ports. But now those ports have been expanded to cover those original devices, plus every USB device, and new Thunderbolt 3 devices but we still only have two ports for all of them.

    The problem is that I am coming from a 2016 MBP, have a ton of USB-C devices/cables already because apple went all in on USB-C a year ago on their laptops, and now they are just treading water with the iMac. Between USB-C and Lightning Apples cable management has been really terrible, I have to have so many different kinds of cables laying around when I am using all Apple hardware all from 2017.
  14. Fishrrman macrumors G5


    Feb 20, 2009
    Thunderbolt 3 isn't going to become any more popular in the computing world (in general) and in the Mac world (in particular) than was thunderbolt 2 before it.

    Which is to say… "not so much".

    USB rules the roost.
    It will continue to do so.
    Even more now that the base speed has been doubled with USB3.1 Gen 2.
  15. Samuelsan2001 macrumors 604

    Oct 24, 2013
    Just another "Apple didn't make a computer specifically for me" well guess what they didn't make a computer specifically for anyone.

    Also it is down to PCIE lanes on the chipset, as others have mentioned, this will not be an issue with the iMac pro and the MacBook pro has used almost all of its PCIe lanes to have four TB3 ports at full speed then again it has no other I/O to worry about.
  16. user1234 macrumors 6502


    Mar 3, 2009
    I agree. I would have wanted to see at least 4 USB-C/Thunderbolt 3 ports, preferably 6. I don't care about type A ports, as I can simply connect my type A hub using a Type-C to type A adapter and solve that problem. I'm more concerned about future use, as an external monitor and a Type-C/Thunderbolt device will use up all available ports.
  17. theluggage, Jul 21, 2017
    Last edited: Jul 26, 2017

    theluggage macrumors 68040

    Jul 29, 2011
    I'm not sure that's going to change: most USB-C devices only need 5Gbps USB 3.1 gen 1 or lower and those will work happily plugged into a USB-A port with a suitable adapter or cable - many of them actually come with a choice of USB-C or USB-A cables anyhow. Apple are still defaulting to USB-A-to-lightning cables for iDevice charging*.

    It's still going to be the same "usual suspects" of RAID arrays and pro A/V interfaces that need the TB3 (or 10Gbps USB 3.1 gen 2) performance competing for the TB3 ports.

    It isn't as if the iMac was ever over-endowed with connectivity options!

    4 TB3/USB-C ports would, of course, be better than 2, but not at the expense of USB-A or Ethernet.

    I'm trying to work out what the difference is between MBP and iMac in this respect. The CPUs have the same number of PCIe lanes. The MBP can drive 5k displays too, so that shouldn't be an issue.

    EDIT: I've tried to look this up and - basically - its non-trivial. If I've got it right then on the 15" MBP/iMac there is a dedicated 16x PCIE bus straight from the CPU to the discrete GPU, then the peripheral controller chip has 26 multi-purpose I/O lanes that the system builder can configure to various permutations of regular PCIe, storage-optimised PCIe, USB, SAT and 1GBPs Ethernet (subject to more constraints than a D&D rulebook). So, yeah, its probably the Ethernet and SATA on the iMac that use the extra lanes.

    The only things I can think of that are in the iMac but not the MBP are the SATA controller for the Fusion drive options (if that's the reason then its rather frustrating for those of us with SSD only iMacs), the Ethernet and the USB-A ports (if that's the reason then I can live with the compromise, although the MBP presumably uses USB internally for the keyboard, trackpad, webcam and touchbar).

    I suspect that, if they'd wanted, Apple could have squeezed in a couple of extra TB3/USB-C ports - even if they were limited to 20Gbps as per the 13" MBP they'd still be fine for DisplayPort. Of course, that would mean adding a second TB3 controller to the motherboard, so maybe they're waiting for a future Intel generation with TB3 built into the chipset (that was expected for Kaby Lake but didn't materialize) - or maybe they just want it as a distinguishing feature for the iMac Pro.

    I'm inclined to agree that this is less of an issue on a desktop machine where any adapters needed are "fit and forget" and you don't have to carry around enough adapters to deal with multiple sets of legacy devices at home, at the office and in meetings. Esp. on an iMac where you'll probably end up with a hub if only to provide front-facing USB ports.

    (*NB, I ordered the Magic Keyboard with num pad and the Magic Trackpad with my iMac - both of which charge via Lightning - but Apple only included one USB-to-lightning cable. Cheapskates!)
  18. Chupa Chupa macrumors G5

    Chupa Chupa

    Jul 16, 2002
    Yeah, I have a 2017 iMac and a 2016 MBP. I find it a bit ironic that I don't care for the 4 USB-C/TB3 ports on the MBP as I don't like dongles when traveling but I desperately need them on my iMac and could not care less if I have to use a dongle on a desktop. I don't really get why Apple didn't just make all the ports on the iMac USB-C/TB3 like on the MBP if it's truly "all in" on the new connector.

    Hopefully very soon there will be a USB-C/TB3 hub. I'm not sure why they don't already exist. At least I've never come across one and I've looked pretty hard.
  19. mrgimme macrumors newbie

    Jul 25, 2017
    Great discussion!

    Question for Dr. Fisherrman: (but others feel free to chime in)
    I have more legacy hardware FW1 audio interface, Fw1 & 2 Drives and TB1 & 2 drives.
    With a 2017 imac would I be better served with a OWC TB2 Dock?
    That FW800 port is ah - ESSENTIAL!
  20. Fishrrman macrumors G5


    Feb 20, 2009
    "I have more legacy hardware FW1 audio interface, Fw1 & 2 Drives and TB1 & 2 drives.
    With a 2017 imac would I be better served with a OWC TB2 Dock?"

    Unless I'm mistaken, you need a "double-dongle" setup to use firewire with thunderbolt 3 Macs:
    1. thunderbolt3-to-thunderbolt2 adapter dongle
    2. thunderbolt2-to-firewire adapter dongle.

    Kludgy, to say the least.

    With a -2015- iMac, all you'd need would be the tbolt2-firewire adapter.

    So... with a 2017 Mac... looks like some kind of dock might be a better way to go (unless there are some "super-dongle/mini docks" that offer a firewire port.

    They're not cheap, though.
    And right now the selection looks to be limited.
  21. mrgimme macrumors newbie

    Jul 25, 2017
    After reviewing the HORRENDOUS Amazon reviews OWC is off the table.

    Kludgy is not what I am looking for.

    I have a 2010 imac running Mavericks. Which I will keep as is- to "serve as dock".

    I can file share on my network for transfers.

    There is certain amount of elegance about using a Mac and if you stray to far into Kludgland you can spend a LOT of time being lost!

    Time to consolidate all those drives and get a solid Thunderbolt 3 storage solution with the money I did not waste on a dock!

    Know of any decent TB3 RAID 0 enclosures for SSDs?
  22. propower macrumors 6502a

    Jul 23, 2010
    I use two OWC TB2 docks via a long TB2 optical chain from my old 2013 MacPro and now for the last month from a 2017 iMac via TB3 to TB2 adapter. Sometimes i have to restart to get all things recognized (may be the device at the end of the chain though). Besides that - very happy with this setup. No FW800 for me though since 2009 :).

    AFAIK - only One TB3 RAID (Akitio) and it has been out of stock all month - with zero reviews... I gave up on that option for now and got a 1TB SSD in the iMac instead. The rest can all be USB3 for now.
  23. theluggage macrumors 68040

    Jul 29, 2011
    One possibility is that the iMac might not have enough internal I/O lanes to go around (unlike the 15" MBP it has to support SATA and Ethernet internally) so if it had 4 ports then - like the 13" MBP - two of them would be speed limited and, if they put more than 4, some of them would be USB/DisplayPort only.

    I think the wheels start to come off the "one port for all" idea as soon as you go to larger laptops and desktops where the space-saving aspect of multi-function ports is less compelling. Personally, I'd have liked one or two MiniDisplayPort sockets so that you didn't have to "waste" a TB3 port to connect a 4k or standard def display.

    Well, until the iMac, TB3 was mostly about laptops, and the overwhelming demand was for something that let you connect your USB-A, DisplayPort and HDMI devices. After all, there's not that much on sale at the moment that requires a USB-C socket (most USB-C external drives come with a USB-C to USB-A cable) and those devices that do are the ones you probably want to connect directly to your computer for max performance.
  24. Fester1952 macrumors member


    Jul 22, 2012
    Adelaide, Australia
    Have you got a link for these reviews for the OWC T3 dock? It is still pre-order. I wouldn't have thought Amazon
    would have them yet and I can't find a review on their website for this dock.
    All the reviews I have read rate it highly.
  25. kwikdeth macrumors 6502a

    Feb 25, 2003
    Tempe, AZ

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