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When USB 4 isn’t Thunderbolt
Thunderbolt 3 hasn’t met with T the success it deserved for SSDs. Ready-made drives remain unusual and expensive, while assembling your own often fails to deliver full performance. However, this now looks set to change with the arrival of USB 4 drives and enclosures capable of higher speeds than Thunderbolt 3, with a larger market to drive prices down.
The standards are a mess, but Thunderbolt 3 only provides 32Gbps for general data, while USB 4 can move a full 40Gbps. In practice, those deliver read and write speeds of less than 3GB/sec to an Intel Mac’s Thunderbolt 3 ports, but well over 3GB/ sec with the USB 4 support of an Apple silicon Mac. Newer USB 4 models don’t fall back to Thunderbolt, though; if they can’t connect using USB 4, they default to USB 3.1 Gen 2 to deliver a mere 1GB/sec to Intel Macs.