Current Generation Hardware Speculation with a Technical Spin [post GDC 2020] [XBSX, PS5]

The whole point of the 7GB/s requirement on the expandaded SSD is so you cN play the games off it.

 

PSman1700 was talking about the internal SSD addition. The one we are all talking about at this moment.

You aren't replacing the 825GB, you are adding to it. Much more simple compared with the PS4.

The external storage via USB is confirmed for PS4 yes.

 

This is what Cerny had said during the road to PS5 stream about the expandability of PS5 SSD

"The kind of storage you need depends on how you're going to use it. If you have an extensive PS4 library [...] then a large external hard drive is ideal. You can leave your games on the hard drive and play them directly from there, saving the pricier SSD storage for your PS5 titles, or you can copy the PS4 titles directly to the SSD. If your purpose in adding more storage is to play PS5 titles, though, ideally you will add to your SSD storage."

It is actually very clear, at least their intention during that time, that you can play your PS4 titles from an external hard drive. If you want to play your PS4 titles from SSD, you can, but it is better to save SSD for PS5 titles. If you want to add more storage to play PS5 titles then you add SSD storage. In this case he said ideally because from what I know you can technically use HDD for PS5 titles, but it will be used as cold storage (vs the nvme SSD where you should be able to play games directly from it).

 

Yes I know about the PS4 titles. I am talking about when we'll add a new SSD in the PS5. I think we won't be able to use the old 825GB SSD to store the games anymore. It makes sense because of their speed requirements, all 12 channels must be dedicated to one SSD.

And, no, what will happen when we'll add another SSD is actually not clear at all.

 

Does not make sense to me and you wont read/write to both at the same time.
So I do not think you are right. And Cerny did use the word add and not replace.

 

Okay. I see where you're coming from with that perspective. We'd need to see more of a logical connection diagram, similar to those shown for motherboards to have a better idea, right? Maybe Sony's controller has double the channels and is split evenly between onboard and expansion. I think that's how the SeriesX|S storage controller is handled, so both can operate at the same time.

 

Re-reading his statement, maybe you are right. I'd love to be wrong!

 

But none of those channels will be shared by the new SSD, they will both just be separate devices on the PCIe bus. To my understanding channels in this context is the 12 lanes from the SSD controller to the individual flash chips as part of that SSD they're not worried about flooding the PCIe system bus or else they wouldn't have added a PCIe expansion option at all.

 

This is also my understanding. PS5 has it's own internal SSD controller for the onboard SSD over one bus, the NVMe drive will connect via PCI 4.x direct to the decompression block in the I/O controller. You ought to be able to use both at the same time for even greater throughput, I can see literally no reason why you can't because if not, how in holy christ will you be move data back and forth between drives? Ditto any external storage connected over the 10Gbps USB connectors.

 

Sorry, are you suggesting I slot in a 1tb and am only 175gb better off? Lol

 

DSoup and Lalaland are correct here. The internal PS5 flash controller is completely unused when accessing the add-on drive. The 12 channels on it connect directly to the soldered-on flash chips, they cannot talk to anything else. Because it's such a source of confusion, here is a quick chart of how the system architecture works:



The system in XSX/XSS is exactly the same except that the internal flash controller is less beefy and that apparently the links connecting to it and the external drive are PCIe 2x 4.0 instead of 4x.

 

Why don't you just listen to what Cerny had to say instead of coming up with some BS?



"Ideally you would add to your SSD storage. We will be supporting certain M2 SSD's. These are internal drives that you get on the open market and you will install into a bay on the PS5.
They connect to the custom I/O unit just like our SSD does. So they can take full advantage of the decompression, I/O co-processors and all the other features I was talking about.
That commercial drive needs to be at least as fast as ours. Games that rely on the speed of our SSD, need to work flawlessly with the M.2 drive."

 

The only thing that cares about those 12 channels is the NAND controller, which sends traffic through PCIe lanes to the SoC. Any SSD you add will have its own NAND controller and its own PCIe lanes and has nothing to do with those 12 channels.

 

Personally I think it is clear that the NVME expansion can be used to play PS5 games directly from it. My biggest question about it is actually the opposite of that. Can you use it not to play PS5 games directly from it? Like if I don't have $200ish for the fastest SSD out there but instead I buy $100ish slower SSD and use it for cold storage? Transferring a 100GB game should take around 30s with 3.5GB/s SSD while using HDD will be much slower and using external SSD (10Gbit/s USB) would take more than 80s. Basically if you are planning to use external SSD for cold storage might as well plug the NVME to the internal M.2 slot.
So it is mainly about what will happen if we plug a random SSD to PS5? will it do a speed check? ID check? will it simply use it for PS5 games regardless of the speed (so you might experience greater load times if the SSD is slow or something)? If they do a speed check/id check and it is not up to the requirements, will it simply not run/unusable?

 

Slower regular disk/ssd can be used to at least play ps4 bc games. If it can be used for cold storage I don't know. I would hope so, it should be pretty easy feature to implement.

 

There's a general consensus on this forum that there will be some kind of check that the system will do to verify the SSD. Now if this is real or not, no one knows. I guess we will find out soon enough as the console is coming out next month.

 

Interesting, there is no clarification on this. You'd probably be better off using a SSD attached to one of the fast USB ports unless yo already have a slower NVMe drive just hanging about ready to slot in.

Yup. Although Sony could support slower drives for storage, as in Rurouni's scenario, but not have the OS qualify the drive sa storage from which PS5 games can run - much like it probably does with external drives. It's not hard to implement but it's still extra effort. Personally I would be surprised if Sony did support this.

 

Cerny specifically said that slower drives can be used for ps4 bc games. The check would likely apply only to ps5 installations.

 

I think it would be very interesting if Sony could let you install any NVMe into the M.2 slot to play PS4 games, but only let you install PS5 games in it if it passed the speed or the list check.