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Our resident genius Howard Oakley solves your Mac and iOS problems
When USB 4 isn’t Thunderbolt
THUNDERBOLT 3 HASN’T met with 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.