Apple updated the USB 4 specs for the 2024 Mac mini and 2024 MacBook Pro. The updated tech specs say the Mac mini with M4 Pro and the MacBook Pro with M4 Pro/M4 Max have three Thunderbolt 5/USB 4 v2 ports each with a maximum USB 4 v2 speed of 120/40 Gb/s (faster speed either sending or receiving) and 80/80 Gb/s (equal speeds sending and receiving). Previously, the tech specs for these products said they have three Thunderbolt 5/USB 4 ports each with a maximum USB 4 speed of 40 Gb/s. Intel and the USB-IF have made USB names so confusing that even the companies implementing it are getting the speeds confused.
Assuming the M4 Ultra is two M4 Max like previous Ultras, the Mac Studio with M4 Ultra should have six Thunderbolt 5/USB 4 v2 ports. This will allow networking four Mac Studios together with all-to-all links where each link is two USB 4 v2 cables. This would provide a combined link speed using two cables of 240/80 Gb/s and no 200 Gb/s network switch is needed. Each Mac Studio with M4 Ultra will have three of these 240/80 Gb/s links. Each link is not exactly the same performance as 200 Gb/s ethernet but it's in the same ballpark (+/- 20%). If macOS doesn't do link aggregation of Thunderbolt 5/USB 4 v2, that would have to be done in the user application or customers would have to settle for a still respectable 120/40 Gb/s network connection between Mac Studios.
A Mac Studio with M4 Ultra will have 24 P cores so four of them will have 96 P cores. A Xeon 6 Granite Rapids processor with 96 P cores costs $10.2K. Graphics cards with performance in the same ballpark as four M4 Ultras probably have a total price of about $7K. An NVIDIA RTX 6000 Ada Generation has a price of $7K. The current Mac Studio with M2 Ultra has a starting price of $4K so four of them would have a starting price of $16K. After adding the graphics cards, memory, storage, power supply, chassis, etc. for the Xeon 6, the total price of the x86 system would be over $16K.
Another use for USB 4 v2 networking is to use one Mac Studio as a file server or compute server connected to 6 client Mac minis. A PCIe Gen 5 NVMe SSD can read 14 GBytes/sec = 112 Gbits/sec. This is a good match for the speed of USB 4 v2. An academic lab or a small startup company where everyone sits at the same table could use this. I haven't found any 120/40 Gb/s fiber optic extension cables but 40 Gb/s fiber optic extension cables are available. If each person has their own office, all the computers could be put physically close together and networked with passive USB 4 v2 cables. Long fiber optic extension cables would be run from each Mac mini to each individual office to connect to a display. The keyboard and mouse would be plugged into the display. What is awesome about this compared to an x86 system is that no 100 Gb/s Network Interface Cards (NICs) and switch are needed. This saves about $9K: $2.5K for seven 100 Gb/s NICs at $360 each plus $6.5K for a 100 Gb/s switch. Shared files would be on the Mac Studio and would be accessed by the client systems (Mac minis).
Assuming the M4 Ultra is two M4 Max like previous Ultras, the Mac Studio with M4 Ultra should have six Thunderbolt 5/USB 4 v2 ports. This will allow networking four Mac Studios together with all-to-all links where each link is two USB 4 v2 cables. This would provide a combined link speed using two cables of 240/80 Gb/s and no 200 Gb/s network switch is needed. Each Mac Studio with M4 Ultra will have three of these 240/80 Gb/s links. Each link is not exactly the same performance as 200 Gb/s ethernet but it's in the same ballpark (+/- 20%). If macOS doesn't do link aggregation of Thunderbolt 5/USB 4 v2, that would have to be done in the user application or customers would have to settle for a still respectable 120/40 Gb/s network connection between Mac Studios.
A Mac Studio with M4 Ultra will have 24 P cores so four of them will have 96 P cores. A Xeon 6 Granite Rapids processor with 96 P cores costs $10.2K. Graphics cards with performance in the same ballpark as four M4 Ultras probably have a total price of about $7K. An NVIDIA RTX 6000 Ada Generation has a price of $7K. The current Mac Studio with M2 Ultra has a starting price of $4K so four of them would have a starting price of $16K. After adding the graphics cards, memory, storage, power supply, chassis, etc. for the Xeon 6, the total price of the x86 system would be over $16K.
Another use for USB 4 v2 networking is to use one Mac Studio as a file server or compute server connected to 6 client Mac minis. A PCIe Gen 5 NVMe SSD can read 14 GBytes/sec = 112 Gbits/sec. This is a good match for the speed of USB 4 v2. An academic lab or a small startup company where everyone sits at the same table could use this. I haven't found any 120/40 Gb/s fiber optic extension cables but 40 Gb/s fiber optic extension cables are available. If each person has their own office, all the computers could be put physically close together and networked with passive USB 4 v2 cables. Long fiber optic extension cables would be run from each Mac mini to each individual office to connect to a display. The keyboard and mouse would be plugged into the display. What is awesome about this compared to an x86 system is that no 100 Gb/s Network Interface Cards (NICs) and switch are needed. This saves about $9K: $2.5K for seven 100 Gb/s NICs at $360 each plus $6.5K for a 100 Gb/s switch. Shared files would be on the Mac Studio and would be accessed by the client systems (Mac minis).
