The PlayStation 5 will support M.2 SSDs up to 2280, Sony confirmed in a recent teardown video. While we still don't have all the details on which of the best NVMe SSDs for PC will make a good fit for the next-gen console, we can at least now confirm that it will support the standard sizing.
There are multiple sizes of NVMe SSD, although most PC builders will be familiar with just one: 2280. Smaller sizes, such as 2260 and 2240, are most often used in compact laptops, and not regularly found in our chunky desktop rigs.
Sony announced the PS5 would feature expandable storage during its first technical overview, although has since held off recommending users go out and purchase an NVMe SSD in preparation for its November 12 (or November 19, for some) release date.
It has long been supposed that this was due to a sizing mismatch between the most common M.2 NVMe SSDs and those which the PS5 would support. However, the recent PS5 teardown posted by Sony confirms otherwise, and clearly shows a single NVMe M.2 expansion slot with support up to 2280 and the most common key (M.2 SSDs also come with different keys, or connector configurations, but you really don't have to worry about that too much).
But while we have all the information we now need on sizing, we still don't know why Sony would rather have you wait to pick up your extra storage drives for the PlayStation 5. Perhaps it's a firmware deal, which would require a little extra work on SSD manufacturers part to ensure compatibility. Sony is using a bespoke SSD controller chip for high bandwidth, so perhaps there's a little more tinkering to be done to bring standard SSDs up to the mark. And don't forget PCIe 4.0 bandwidth will very likely be a part of that requirement.
We still don't recommend you rush to buy one of the best NVMe SSDs in a flash, but at least there's hope your spare PC drive may come in handy in bolstering the 825GB (perhaps more like 664GB with system reservations) internal PS5 SSD.