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'Thunderbolt 5' Would Enable Dual 8K Display Support and More on Macs
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That’s not true. Thunderbolt is a tunneling protocol. It tunnels usb, DisplayPort and pcie. the egpu enclosures connect to apple silicon machines but if the pcie device (gpu) doesn’t have a driver then nothing happens. I have connected an egpu to my apple silicon Mac with a 10 Gbps lan card in the slot. And it comes on.
But I agree, we're unlikely to ever see Radeon ARM drivers on macOS.
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Dual 8K displays on a Mac, will that be the resolutions or the prices?
I'm impressed with how much they can squeeze through a Thunderbolt cable.
Bet it irks Apple that they actually don’t own Thunderbolt….and that they screwed up the “idea” of Lightning by not further developing it further themselves.
Eventually, seeing the limited use Thunderbolt actually has (let’s be honest, USB has improved so much that for 90% of us it exceeds every use case). Apple will drop Thunderbolt in a “brave” move and release something of their own for those 10% of us who actually need that speed.
Eventually, seeing the limited use Thunderbolt actually has (let’s be honest, USB has improved so much that for 90% of us it exceeds every use case). Apple will drop Thunderbolt in a “brave” move and release something of their own for those 10% of us who actually need that speed.
That's just a software issue. I have a 5k 27" iMac, and my mouse pointer is plenty responsive. But I use a Logitech G502 Gaming Mouse and set the pointer for fast tracking speeds using Logitech's Gaming Software. I then combine it with the Decelerator app to slow down the tracking speed when I'm moving slowly, giving me a combination of fast movement when I'm moving across the entire screen, and slow movement when I need to be more precise.
The tracking speed adjustability in MacOS is more limited, but the next time you're at the Apple store, go to System Preferences > Mouse, and set the Tracking Speed to to the fastest setting.
The Ventura beta includes support for the Dell UP3218K 8K @60,48,30, and 24 Hz on the Mac Pro. Looking forward to seeing if that makes its way into the stable release:
I see Intel plans on a load balancing option to use 3 lines in transmit (120 Gbps) and 1 line in receive (40 Gbps). I posted this idea awhile ago. I also thought it would be possible to add another couple lines using the USB 2.0 lines but I guess that's more difficult (requires new cables) than just increasing the bandwidth of each line. It will probably use PAM-3 like USB4 2.0 does. USB4 wikipedia calls the 120Gbps mode "Asymmetric" and the normal mode is "Symmetric".
Thunderbolt 3 can probably already do dual 8K 60Hz using DSC@8bpp at up to 2090MHz (less than the 2376MHz used by HDMI). Currently Apple uses DSC@12bpp for the Apple Pro Display XDR and Apple Studio Display. I don't know what DSC@8bpp looks like.
8K30 was possible with the Dell UP3218K with a display override (Intel Mac only).
Apple added 8K60 support for the Dell UP3218K in Ventura for certain Mac Pro models. There's a patch to make it work with any Intel Mac. The Dell UP3218K is an old display that doesn't support DSC. It uses two tiles of 3840x4320 which can't be connected to a single Thunderbolt port unless you could get two MST hubs each running at HBR2 link rate to decompress a 3840x4320 DSC stream. macOS support for DSC is kind of broken after Catalina (only works for Apple's displays?)
8K30 might work using HDMI 2.0 at 8bpc 4:2:0. I've seen people get 8K60 using DisplayPort 1.4 to HDMI 2.1 adapters on Intel Macs - but macOS doesn't enable DSC so this is also using 4:2:0 to squeeze through the DisplayPort 1.4 non-DSC bottleneck.
Thunderbolt bandwidth is ≈22Gbps for PCIe data. The rest of the 40 Gbps can be used by DisplayPort. For example, the Apple Pro Display XDR when used by an Intel Mac that supports DisplayPort 1.4 but not DSC will use 39 Gbps.
Apple's 5K and 6K displays don't allow daisy chain because they have a dual tile mode that uses the second Thunderbolt output of a Titan Ridge Thunderbolt controller to provide a second DisplayPort signal for the other half of the display. The dual tile mode is for compatibility with Macs that don't support DSC. I suppose Apple could replace the Titan Ridge controller with a Goshen Ridge controller - that would allow dual tile mode for non-DSC Macs and DSC mode + chaining for DSC Macs.
LG UltraFine 5K display has a dual tile mode for 5K60. It doesn't support DSC or HBR3 so single tile mode is limited to 4K60 or 5K39 (with custom timing on Intel Mac). Using a single tile mode allows connecting two displays to a Thunderbolt hub. You can do that with Apple's 5K and 6K displays.
M1 Macs have Thunderbolt ports that allow PCIe tunnelling (allows using externally connected NVMe, Ethernet, USB, SATA, etc. controllers). You can connect a GPU but Apple has not created third party GPU drivers that work on non-Intel Macs.
Not DRM. DMA. Apple uses the Thunderbolt 4 name for the Macs with M1 Pro/Max/Ultra chips which means their DMA protection, while not using Intel VT-d, is sufficient.
Apple M1 and M2 Macs have all the features of TB 4 except they don't support two separate 4K60 displays from a single Thunderbolt port so they can't be called TB 4. M1 Max, Pro, Ultra do support multiple displays per Thunderbolt port so they can use the Thunderbolt 4 name.
While the non-Max,Pro,Ultra M1 and M2 Macs don't support two displays from a single Thunderbolt port, they do have two DisplayPort connections that allow connecting a dual tile display such as the LG UltraFine 5K or Dell UP2715K. The second DisplayPort connection cannot be used for a separate display.
Naively, it seems that switching from the 2-level (binary) system used in TB4 to a 3-level (ternary) system like PAM-3 isn't, by itself, going to give them twice the bandwidth. They'll also need to increase the frequency by 25%:
If the word length in a binary system is x bits, then that encodes for 2^x values. To determine the number of bits, y, that would give you the same no. of values in a ternary system, you'd just solve 3^y = 2^x, giving y = x * ln(2)/ln(3) = 0.63 x. I.e., you'd need 63% as many bits, giving 1/0.63 = 1.6 times the bandwidth for the same frequency with a ternary system as compared to a binary system.
Thus to get twice the bandwidth, you'd additionally have to increase the frequency by a factor of 2/1.6 = 1.25.
Do I have that right?
Just imagine how many kidneys Apple will charge for an 8K display, much less two.
They used to be on the forefront of relatively affordable advanced display technology. 5K was so far ahead of it's time that most PCs still haven't caught up. And it included a full computer! Yet 6K in a simple display is this unattainable thing for most people that starts at many thousands of dollars.
I don't even care about 8K at this point. I just want to be able to buy and run a single 32" 6K HDR600 120Hz display from Apple for under $2500.
They used to be on the forefront of relatively affordable advanced display technology. 5K was so far ahead of it's time that most PCs still haven't caught up. And it included a full computer! Yet 6K in a simple display is this unattainable thing for most people that starts at many thousands of dollars.
I don't even care about 8K at this point. I just want to be able to buy and run a single 32" 6K HDR600 120Hz display from Apple for under $2500.
It gives you 4K HiDPI resolution. It looks fantastic with the pixel density while offering a much better resolution.
With DSC (also used by Pro Display XDR now) it is possible to drive 8K (7680 × 4320) at 144Hz with DisplayPort 2.0 and 2.1 without subsampling. For 120 Gbit/s I could presume it could drive dual 8K at 120Hz.
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Other manufacturers are allowed to produce 8K monitors, as they have already been doing.
We have had the Dell UP3218K since 2017 and the ViewSonic VP3286-8K might soon come with TB4.
The only real missing piece to the puzzle is the total lack of 8K support on Apple Silicon.
Very close. The USB4 2.0 spec was just released (Thunderbolt 5 announcement purposefully coincides?). It says it uses PAM3 at 25.6 GB (B=baud because it's not transmitting bits). "Each PAM3 bit encodes 1.57 bits obtained through 11-bits to 7-trits mapping". I guess a trit is a PAM3 three-level bit. First time I've seen that term. Each trit takes 39.0625 picoseconds.
USB4 1.0 (gen 3) uses 20Gbps. 128b/132b encoding.
Thunderbolt 3/4 uses 20.625Gbps 64b/66b encoding.
The USB4 2.0 spec also has a lot of DisplayPort 2.0 info.
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Why are you complaining about Apple’s prices rather than that competitors aren’t even trying (other than the LG Ultrafine)?
As I recall, 21-inch CRTs were basically as large as it got in the mid-90s, at 1600x1200.