Despite news that both Microsoft and Sony would be using PCIExpress 4.0 NVME SSD drives for their next-generation consoles' main storage drive -- speeding up game load times and play speeds immensely -- the Sony one might be way, way faster. Although we don't know for sure which drives each company is using in their new consoles, the one in the new Xbox may well run at only PCIE 3.0 speeds.
This is all because of the controller. According to a LinkedIn post by a former Phison employee (via PCGamesN), Microsoft is using the Phison PS5019-E19T controller, which is a PCIE 3.0 controller that works with PCIE 4.0. That means it runs at PCIE 3.0 speeds. That's fast, maxing out at 3,700MB/s and 3,000MB/s for sequential read/write respectively, but it's not PCIE 4.0 speeds, which can reach 5,000MB/s and beyond.
Now, the big caveat here is that this ex-employee hasn't had access to release Xbox hardware. Nobody outside of Microsoft does yet. That means that the Phison controller is the one used in the developer version of the Xbox Series X. That could be a placeholder chip while new controllers were developed, potentially giving the Series X just as much storage performance as the PS5.
But even if that's not the case, maybe we shouldn't be greedy. Finally, console manufacturers are catching up to PCs on the storage front. We're going to get faster drives in these systems than most high-end gaming PCs enjoy, because as this time there's not a real need for NVME storage (it typically only speeds up game loads times by a second or so). But with new gen consoles having them in every variation, that could make them a much more needed buy moving forward.
