The base level 14-inch M2 MacBook Pro reportedly has a slower SSD than its predecessor, according to tests done by 9to5Mac. In BlackMagic’s Disk Speed Test, the 512GB SSD in Apple’s latest flagship achieved read speed scores of around 2,970 MB/s and write speed scores of around 3,150 MB/s, compared to 4,900 MB/s reads and 3,950 MB/s writes that the M1 Pro with a 512GB SSD was capable of.
The reason for the difference is likely down to chips. According to 9to5Mac, the 512GB SSD in the previous-gen 14-inch had four NAND storage chips, whereas the one on the M2 Pro seems to have two. Those are obviously higher-capacity chips, so the computers have the same amount of storage but with worse performance because they can’t parallelize reads and writes as much.
Building newer generations of computers with fewer NAND chips isn’t new for Apple. Both the 256GB M2 MacBook Air and 13-inch MacBook Pro had slower storage than the M1 versions of those machines. (The situation was even worse with those machines, which had a single NAND chip.) But those are relatively entry-level laptops; the 14-inch MacBook Pro is a $2,000 computer aimed at creative professionals and developers — it’s not a place you’d expect Apple to cut corners or sacrifice performance.