While the new Mac mini with the M2 chip has a lower $599 starting price, the base model with 256GB of storage has slower SSD read and write speeds compared to the previous-generation model with the M1 chip and 256GB of storage.
A teardown of the new Mac mini shared by YouTube channel Brandon Geekabit reveals that the 256GB model is equipped with only a single 256GB storage chip, while the same configuration with the M1 chip has two 128GB chips. This difference explains why the new model has a slower SSD, as multiple NAND chips allow for faster speeds.
We have confirmed with the Blackmagic Disk Speed Test benchmarking app that SSD read and write speeds for the new 256GB Mac mini are each around 1,500 MB/s, which is anywhere from 30% to 50% slower than read and write speeds for the equivalent previous-generation model, although benchmark results and real-world performance can vary.
Customers who are looking for the fastest SSD speeds should ensure they configure their M2 Mac mini with at least 512GB of storage to avoid this issue. A slower SSD can impact file transfer speeds, and overall performance can also take a slight hit since Macs temporarily use SSD space as virtual memory when physical RAM is fully used.