Though it will utilize DirectStorage to help make up the difference in performance.

The system requirements for the upcoming PC release of Ratchet & Clank: Rift Apart were shared earlier today in a now deleted Steam blog post. There are five separate configurations offered that show what sort of performance level you can expect.

Notably, the absolute minimum configuration isn't using an SSD as you would expect, but rather one of those dusty (and probably smelly) HDD. You know, those big things that have spinning platters inside and are rather slow in comparison to SSDs? Those things.

The PC system requirements for Ratchet and Clank: Rift Apart across a variety of hardware configurations.

You can use an HDD if you so desire, but it's not recommended. This is only for those that are merely hoping to play the new platforming action game at 720p resolution and 30FPS with everything turned to very low.

The catch here is that Ratchet & Clank: Rift Apart will make use of DirectStorage 1.2. Here is what principal programmer Alex Bartholomeus said in that initial blog post about how DirectStorage 1.2 will be utilized on both HDDs and, of course, on SSDs.

For Ratchet & Clank: Rift Apart on PC we added adaptive streaming based on live measurement of the available hardware bandwidth. This allows us to tailor the texture streaming strategy for the best possible texture streaming on any configuration. With DirectStorage, the use of a fast NVMe SSD and GPU decompression, this results in very responsive texture streaming even at the highest settings.

DirectStorage is developed to fully utilize the speed of fast PCIe NVMe SSDs, but the technology is also compatible with SATA SSDs and even traditional hard disk drives. This means Ratchet & Clank: Rift Apart on PC can use the same technology for loading data, regardless of the storage device in your system.​
Seeing the base requirement including a HDD is kind of amusing though. Back in 2020, Insomniac and Sony said that Rift Apart just wouldn't be possible without the PlayStation 5's SSD. Here is what Insomniac's creative director Marcus Smith said at the time.

The SSD is screamingly fast. It allows us to build worlds and project players from one place to another in near instantaneous speeds. It is an unbelievable game-changer in terms of we can now do gameplay where you’re in one world and the next moment you’re in another. We’re loading up levels and that happens so quickly and in the action that you don’t even imagine that this is something we couldn’t do before, because it feels so natural. Long gone are loading screens. Now it’s all about bringing exciting new adventures.
Let's make something very clear here: You are not going to have the same experience playing this game on a HDD as you would if playing on an SSD. DirectStorage 1.2 will only be able to do so much before it runs into the limitations of the hardware inside of your machine. When push comes to shove, things like levels, assets, and textures are still going to load faster on machines where SSDs are used. DirectStorage will help those machines with HDD but it won't perform miracles.

Ratchet & Clank: Rift Apart arrives on PC on July 26, 2023.