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Thunderbolt 5 in New Macs: Features, Benefits, and Is It Needed?
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Can someone please clarify which processor I require to power 2 x 4k displays from a single thunderbolt port? I want to use a thunderbolt 4 or 5 dock and connect a single cable to my MacBook to run the two monitors, just like I do with my windows (work) laptop. Apple support gives me a different answer every time I ask.
Nope, apple will sell their (currently 10 years old) 60Hz SDR lcd panels until 2030 and continue to charge $3000 until the day they are discontinued.
Meanwhile the rest of the world will probably be on 480Hz 4K OLED with 5000+nit HDR for like a grand.
i dont think so
tb5 is a total novelty without any real use case for forseable future. theres zero reason to put it in Macs this early unless they need it for their own products.
and 60 Hz limit has been a major issue with those for a lot of people who wanted to buy them, me included. people just didnt realized it was a connector issue, and not a panel issue, or apple's choice to limit those for profit.
or, to use your own reasoning, if they wanted to overcharge people for 60hz panels, they've might as well overcharge them for TB4 and make TB5 selling point of some future Macs down the road.
I might add asking is that speed theoretical or even achievable, given just because a port has a bandwidth of X, that only matters if the bus can supply the port at X speed. Shoving a 10gbe port in an 1st gen Intel NUC, doesn’t mean it can saturate a 10-gb Ethernet. And is there anything left on the bus to do any other tasks? Especially on a Mac where the video memory is shared.
It is like I was doing a massive data enrichment task on a database and running single threaded was going to take 10 days or so on my monster x86 based workstation, and I was getting a lot of heap fragmentation, so quickly rewrote the code to use all 24 cores as threads (it’s essentially an extremely complex SIMD task) and of course my machine froze because there was no core left to handle the UI, I managed to kill the job and changed it to use 23-cores… dropped it to about 30 hours.
This seems like the computer version of “how can I be out of money, I still have checks in my checkbook?”
I really hope so. Apple has really neglected their line of displays for a long time. I would like to see a few at various price points and sizes, but we have exactly one pro display at an eye-watering price, and one premium consumer display and they're very rarely (if at all) updated.
Even just the base M4 can do that now, contrary to the M3 before it. That is exactly why the M4 now has Thunderbolt 4 ports and not like the M3 only Thunderbolt/USB 4, because the ability to drive two 4k displays from the same port is exactly what sets the Thunderbolt 4 certification apart.
please note that they need to be TB4 displays
USB-C displays (ie Dell 4k displays) daisy chaining does not work on Apple devices
I see a ton of oversized 4K displays out there and not much else. What I want is a true retina 5K display that plays well with the Mac's scaling. Not a ton of options for that -- and it gets even worse if you don't want something that looks nice on the desk. I know, I'm being crazy picky here, hence my wish for Apple to fill out their offerings.Get a better one cheaper from a different vendor then. No fuzz
Asus recently put out a 5K ProArt 27" display that's getting good reviews; it's got some anti-glare on the screen which might bother someone determined to have glossy. IIRC, the stand is plastic not metal. I've yet to see a review of a monitor with in-monitor speakers on par with the Apple Studio Display. It's not Thunderbolt and has no webcam or Center Stage.
But it's $800 and judging from reviews has exceptional color accuracy.
If you don't like Apple's premium pricing on displays (and I don't), what are you willing to give up on the ASD to bring the price down? The sturdy metal, industrial 'chic' look? The excellent in-monitor speaker system with spatial audio? The built-in webcam with Center Stage? Thunderbolt?
If an Apple staffer reads this thread and sees your post, what should he recommend to the engineering and marketing people to appeal to you and like-minded folks?
Oh, and the ASUS stand has a nice range of adjustments without having to pay an exorbitant extra cost, and non-Apple displays tend to have HDMI, play well with Windows PCs also, and so have their own perks.
You must be new to apple hardware, their track record for updating displays and pricing can only be described as painfully abysmal.
Also apple isn’t adding anything early, tb5 spec has been ready for about a year, they added tb4 in the same timeframe. More likely the old tb4 controllers are being phased out and it’s easier and cheaper(or costs the same) to use the new one, or possibly they have no choice.
Here is the right answer from caldigit, perhaps the easiest way to understand external monitor support on Macbook
just look into the number of thunderbolt ports on your Macbook, then you can instantly get an idea how many moitors can be supported from a single thunderbolt 3, 4 or 5 dock.
Actually, Intel has newer Thunderbolt 4 controllers (JHL9540, JHL9440) that have PCIe gen 4 and DP 2.1. Maybe they're Thunderbolt 5 except capped at 40 Gbps. They are part of the Barlow Ridge family which includes the Thunderbolt 5 controllers. These Intel Controllers support 3 DisplayPort inputs or outputs, which is up from the usual 2. Does Apple Silicon support 3 displays from a single Thunderbolt 5 port? Thunderbolt 4 requires the ability to output two 4K displays. Did Intel change this for Thunderbolt 5? There's a Intel techbrief that says only Dual 6K is required. So Apple could limit Thunderbolt 5 single port output to two displays.
That is correct, but you can also use a Thunderbolt dock or hub if it is able to deliver the two separate Display Port streams to two separate output ports, as it should be, so the 4k displays themselves don't need to deal with Thunderbolt at all.
No, Apple is using their own Thunderbolt controllers directly integrated into their SoCs and only use external driver/retimer chips.
Sorry I don't think you will see a 0GB bus powered enclosure (at least that is Intel certified) for a while due to power draw requirements. Keep a lookout though for other stuff in the near future from us
and followed ... good to see a representative (however (un)official) from OWC here. Feature request for a TB5 dock with active cooling for 2-4 M.2 SSDs. Happy to participate in any "beta" testing
Use case exists today. 6GB/sec speeds from an SSD I already own and currently taps out at 3.2GB/sec, nuff said. To anyone wanting to work with large media files without paying Apple's exorbitant fees for storage is enough reason to upgrade to M4 Pro/TB5. This feature alone is the reason I am planning on buying the MacBook Pro with the M4Pro.
Will most users need this feature, no. Will lots of media professionals jump on this, abso-effen-lutely.
Ha as official as it might get on a forum like this. At least you're hearing directly from one of the engineers here
You are close here, but one issue is how the chipset bifurcates the PCIe lanes.
On TB3, there was 1 upstream, 1 downstream, a 10G USB lane, and 4 lanes of PCIe 3 to the device itself. Those 4 lanes could be used for SSDs and PCIe peripherals. They could be configured as x1,x1,x1,x1 or x2x2 or x4. They could also be used with PCIe to USB peripherals. EG, our TB3 dock has three PCIe to USB chipsets in it.
On TB4, there is 1 upstream, up to 3 downstream, a 10G USB lane, and 1 lane of PCIe 3 to the device itself. In a dock, pretty much all non TB ports go over the USB lane. Some companies use the 1 lane for Ethernet, most don't use it at all, some use the lane for an SSD (like the ministack STX).
In TB5, there is 1 upstream, up to 3 downstream, a 10G USB lane amd 4 lanes of PCIe 4 to the device itself. Best of both worlds from TB3 and TB4, right?
But there is one "catch" to this with TB5. If you want 3 downstream ports, the configuration/bifurcation of the PCIe lanes are as follows ONLY:
x2,x2 (I think can run as x1,x1 or x2,x1 too, but not split to three)
x4
If you want to bifurcate those PCIe lanes into x1,x1,x1,x1, then you can only have 1 upstream and 1 downstream TB port. You also can't bifurcate to something like x2,x1,x1.
In a dock, people want the following ports it seems: 10G ethernet, CFexpress Type B, CFexpress Type A and internal NVMe ssds. These all require PCIe. 10G uses 1-2 lanes of PCIe 4, CFX B uses 2 lanes of PCIe 4 and CFX A requires 1 lane of PCIe. So to continue this thought, if you wanted a 10G ethernet port AND a CFexpress reader, there are no lanes for PCIe to USB controllers or PCIe for NVMe.
In fact, you can only have two of the following to choose from: 10G Ethernet, CFXB, CFXA, NVMe SSD, PCIe to USB chipsets. So for TB5, you will likely see all USB ports sharing the same bandwidth that TB4 allowed for. Which is one of the reasons to go with a TB5 hub + your current TB4/3 dock.
Thank you; Very interesting! 😃
Since Thunderbolt is a tunneling protocol and is known to tunnel separate Display Port streams and a bundle of PCIe lanes, I'm unsure about some details:
1. Is there actually a separate USB stream tunneled from the host as well, separately from the PCIe stream to be unwrapped to daisy-chaining downstream ports when an USB device is plugged in there? And if so, a Thunderbolt dock with multiple downstream ports would then have to contain its own USB hub to split that connection?
2. a) I'm not entirely certain about how PCIe switches work in detail, so if a dock contains multiple PCIe peripherals but those are used only occasionally, is the remaining PCIe bandwidth then still available to downstream devices via a PCIe switch in the dock? Is bandwidth dynamically allocated as needed (probably with priority for upstream users) or statically at startup/plugin time?
2. b) if bandwidth needs are low enough, can't a PCIe lane bundle be split up via switch into multiple slower PCIe lanes and so effectively share the resource? Is that usually only avoided due to cost or is that actually not possible?
2. c) Is there no 1x/1x/1x/1x PCIe split available in TB5?
3. Does TB5 now tunnel more than 2 Display Port streams and can available chips for docks extract those at the same time to separate ports? Do M4 Pro and Max actually support that by providing more than just 2 Display Port streams per port?
4. Are there more stream types tunneled through Thunderbolt (5) than just PCIe, Display Port and possibly USB?
Yes, thats how it works on pretty much every single Thunderbolt 4 dock/hub! When a company releases a 22/18/XX number of port docks, the bandwidth is split up as such: 3 downstream ports get full bandwidth of course shared if used together, 1 lane of PCIe either not used or used for 2.5g ethernet these days, a 10G usb hub. All non-display ports and non TB ports and most ethernet ports share a single 10Gbps USB connection. Docks have a USB hub chipset to distribute that bandwidth. Some have more than 1. More ports just means bottlenecking more devices in a small pipe!
Most docks do not contain a PCIe switch. Actually most Thunderbolt devices do not contain any separate PCIe switch. They are super expensive! When you want more lanes than what are available though, then you need a PCIe switch. You'll see a PCIe switch in the following OWC products: Flex 8, Flex 1u4, Thunderblade X8. Those have more PCIe devices than what standard TB can offer. And since TB4 only offers 1 lane of PCIe within the device, these are all Thunderbolt 3 devices! Fun fact, a TB4 Thunderblade would be 4x slower than a TB3 one.
Bandwidth is allocated physically by traces on the motherboard, or through a PCIe switch. Downstream ports are of separate- I mean yes there is a overall 40Gbps cap on TB. If say you had a dock with 10G ethernet (OWC Pro Dock) and a SSD plugged into the downstream port of the dock, both would be sharing the overall bandwidth. If you had no traffic on the ethernet port, the SSD would consume as much bandwidth as it can. Add traffic to the 10G ethernet port and they have to share that overall 40Gbps pipe (of which like 22-24Gbps are for data, the rest pretty much reserved for displays).
There is this split of x1,x1,x1,x1 of TB5 (Barlow Ridge) but if this is how a device is designed, there can only be 1 upstream and 1 downstream port. If you want 1 upstream and 3 downstream or 1 upstream and 2 downstream, the only configurations that are possible are x2,x2 or x4. I believe a x1 device can use the x2 lane though, which is why you could have a dock with CFexpress B and CFexpress A, while CFexpress A is only 1 lane. You cannot though have a dock with 10G ethernet (1 lane), CFexpress B (2 lane) and CFexpress A (1 lane). Adds up to 4, but not a possible configuration.
Honestly I don't know a ton about the display side of things. I would follow the specs of our hub: https://www.owc.com/solutions/thunderbolt-5-hub
You can already do 2 monitors via a single Thunderbolt 3 port. I believe 3 can be done over the TB5 port but don't quote me on that. Keep in mind, the more displays/pixels/refresh rate used, the less bandwidth to PCIe and USB devices. The pipeline diameter doesn't change.
Not sure what you mean here? TB5 tunnels PCIe, DP and USB. What else would there be to tunnel?
Also here is an explanation of TB3 vs TB4:https://www.owc.com/blog/whats-the-difference-between-thunderbolt-3-and-thunderbolt-4
And here is a good diagram of TB3 bandwidth I found on a macrumors post: https://forums.macrumors.com/thread...orage-read-write-speeds.2340127/post-32086143