Some customers discovered that storage speeds were actually significantly slower than they were on the M1 models when Apple updated its Macs with the M2 processor. When compared to M1 Macs with equivalent storage capacities, the storage rates of the 512GB M2 MacBook Pro and the 256GB M2 MacBook Air were almost half as fast.
This was caused by Apple employing less actual flash memory chips to supply the same amount of storage, teardowns showed. By simultaneously reading from and writing to many NAND flash chips, a technique known as “interleaving,” modern SSDs are able to operate at very fast speeds. Speeds decrease when there’s only one flash chip to access.
It appears that Apple may have changed its mind on this, at least for some Airs, based on early disassembly of the M3 MacBook Air. After disassembling a 256GB M3 Air, the Max Tech YouTube channel revealed two 128GB NAND flash chips in place of the one 256GB chip found in the M2 Air. Performance on the BlackMagic Disc Speed Test rises in line with this; the 256GB M2 Air achieves read and write speeds of about 1,600 MB/s, while the M3 Air achieves read and write speeds of about 2,900 MB/s and 2,100 MB/s, respectively. That’s about in line with the performance of the M1 Air.
The storage speed of the remaining M3 MacBook Airs ought to be largely identical to that of the M2 models. We received the 512GB model of the 13- and 15-inch M3 Airs from Apple, and the storage performance in the BlackMagic Disc Speed Test was approximately 3,000 MB/s for both reading and writing, which is similar to the 512GB M2 Airs.
While this seems to be good news for consumers of M3 Air models, it is not a guarantee that any particular 256GB MacBook Air model would be delivered in this configuration. Since Apple sources many of the parts for its products from several suppliers, it may send a variety of 128GB and 256GB CPUs in distinct 256GB MacBook Airs depending on whether parts are more affordable or easily accessible at any particular time. (The Max Tech channel theorises that Apple pays more for a single 128GB NAND chip than for a single 256GB NAND chip; however, the channel doesn’t provide a source for this; also, we are unaware of the pricing Apple bargains with its suppliers for these parts.)
It’s unfortunate that a new Air device only offers the same storage speed as the M1 Airs, which were released more than three years ago, despite the fact that it’s good that the M3 Air’s baseline storage speeds are rising. It’s disappointing that Apple is unable to enhance GPU and CPU performance in tandem with storage speeds, particularly since that common M.2 SSDs found in PCs are becoming more affordable and quicker than those sold by Apple in its Mac series.
