Why the SSD is a big deal for PS5, Series X.

[DonFerrari]

Hiku said:

One thing I'm a bit confused about.
What exactly is it that makes the PS5 SSD able to function as RAM? It's not just the speed, I'm sure. Because Cerny said that other commercial SSD's will need to be faster than the PS5 SSD's 5.5 GB in order to work on PS5.

Is it the custom I/O unit?

Or the flash controller giving the PS5's SSD 6 true priority levels instead of 2 like other SSDs?
He mentioned that the custom I/O unit would need to make up for the lack of true priority levels on industry SSD's, instead of that drive's flash controller.

I would say it is the controller. Because even old PCs with slow HDD used that for "cache" as some virtual RAM.

So when SSD is very fast on PS5 it can help the RAM without being an issue for the performance I guess. There is also the coherence unit that will support the fill and removal of data from the RAM and that is on the SSD solution.