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Only for the 256GB model, though

Apple’s latest M2 (opens in new tab) 13-inch MacBook Pro laptops contain a significantly slower SSD - or at least one putting out slower transfer rates - than the equivalent M1 models. The discovery was reported by MacRumors (opens in new tab) and builds on the work of YouTube channels such as Max Tech (opens in new tab) and Created Tech (opens in new tab).Tests using Black Magic’s Disk speed Test app showed the M2 MBP’s 256GB SSD achieving read and write rates of around 1,450MB/s, which knocks 50% off the read speeds of the M1 MBP’s 256GB SSD. The write rate also decreased by 30%.

Of course, someone had to take an M2 MacBook Pro apart and see what was going on. This person was Vadim Yuryev of Max Tech, who discovered the M2’s SSD uses a single 256GB NAND chip, compared to the pair of 128GB chips in the M1. The older unit would have been accessing both chips in parallel, allowing for the higher transfer speeds of 2,900MB/s.

Tests on the 512GB model from a MacRumours forum (opens in new tab) member achieved a transfer rate similar to that of the M1 models, suggesting that this SSD is made up of a pair of chips, and only the entry-level 256GB SSD is affected. 

The use of a single chip in place of the usual two is probably a cost-saving measure, or it may be connected to the global shortage of electronics (opens in new tab). Either way, it will affect the performance of your Mac in several ways, both slowing down file transfers and constraining performance generally as the Mac swaps data in and out of RAM to the SSD as part of its virtual memory system. Upgrading your MPB to a 512GB SSD can only be achieved at the ordering stage, and adds $200 to the price of the laptop.

The 13-inch MacBook Pro is the first of Apple’s Pro laptops to move up to the M2 chip (opens in new tab), with the 14- and 16-inch models still using M1 Pro and Max CPUs. The 13-incher is, however, limited in the number of ports it exposes to the world, with only a pair of USB-C ports and a headphone socket, compared to (opens in new tab) the larger Macs’ three USB-Cs, a Mag-Safe charging port, full-size HDMI and SD card slots. The 13-inch model also retains Apple’s controversial Touch Bar. A new M2 version of the MacBook Air is expected in July.
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