Sony details specs for PS5, including SSD, backward compatibility
Consoles
There'll be lots of chances later on this year to look at the PlayStation five games.
Today I want to talk a bit about our goals for the PlayStation five hardware and how they influenced the development of the console.
To me the SSD really is the key to the next generation.
It's a game changer.
And it was the number one ask from developers for PlayStation5.
As in, we know it's probably impossible but can you put an SSD in it?
I want to focus in on just one number here, which is how long it takes to load a gigabyte of data.
From a hard drive, the difficulty being that hard drives are neither particularly fast nor flexible.
If all your data is in one block, which is frankly not very likely, you can load 50 to 100 megabytes a second.
Depending on where the data is located on the hard drive.
Let's assume it's on the outer edge, which means loading a gigabyte Takes 10 seconds.
If you compress your game packages you can fit more data on the blu ray disc and also effectively boost your hard drive read speed by the compression ratio.
We support z lib decompression on PlayStation four that gets you something like 50% more data on the disk and 50% higher effective read speed Unfortunately though, it's highly likely that your data is scattered around in various files on the hard drive, as well as sourced from multiple locations within those files.
So lots of seeks are needed at two to 50ish milliseconds each.
My rule of thumb is that the hard drive is spending two thirds of its time seeking and only a third of its time actually loading data.
Putting all that together, a gigabyte is very roughly 20 seconds to load from a hard drive.
Now, a gigabyte is not much data.
Games are using five or six gigabytes of RAM on PlayStation four.
So boot times and load times can get pretty grim.
Where to put that differently.
As a player, you wait for the game to boot, wait for the game to load Wait for the level to reload every time you die and you wait for what is euphemistically called fast travel.
And all of that leads to the dream.
What if we could have not just an SSD.
But a blindingly fast SSD.
If we could load five gigabytes a second from it, what would change?
Now SSDs are completely different from hard drives.
They don't have seeks as such.
If you have a five gigabyte a second SSD, you can read data from 1,000 different locations in that second pretty much at speed As for time to load a gigabyte, this is next gen we're talking about.
So memory is bigger.
Instead, we should be asking how long to load two gigabytes.
And the answer is about a quarter of a second.
That's amazing.
We're talking two orders of magnitude, meaning very roughly 100 times faster.
Which means at 5 GB/s for the SSD the potential is that the game boots in a second, there are no load screens, that a game just fades down while loading a half dozen gigabytes and fades back up again.
Same for a reload, you're immediately back in the action after you die.
And fast travel becomes so fast it's blink and you miss it.
As game creators, we go from trying to distract the player from how long fast travel is taking, like those Spider-Man subway rides, to being to blindingly fast that we might even have to slow that transition down.
Now, backwards compatibility was handled masterfully by AMD.
They treated it as a key need throughout the design process.
As our solution to adding new features without blindsiding developers we made sure that if there were new significant features it would be optional to use them.
The GPU supports ray tracing, but you don't have to use ray tracing to.
To make your game the GPU supports primitive shaders, but you can release your first game on PlayStation five, without making any use of them.
And the PlayStation five GPU is backwards compatible with PlayStation four.
What does that mean?
One way you can achieve backwards compatibility is to put the previous consoles chipset in the new console like we did with some PlayStation threes, but that's of course, extremely expensive.
A better way is to incorporate any differences in the previous consoles logic into the new consoles, custom chips, meaning that even as the technology evolves, the logic and feature set that PlayStation four and PlayStation four pro titles rely on is still available in backwards compatibility modes.
One advantage of this strategy is that Once backwards compatibility is in the console it's in.
It's not as if a cost down will remove backwards compatibility like it did on PlayStation three.
achieving this unification of functionality took years of efforts by AMD Any roadmap advancement creates a potential divergence in logic.
Running ps4 and ps4 titles that boosted frequencies has also added complexity.
The boost is truly massive this time around and some game code just can't handle it.
Testing has to be done on the title by title basis.
Results are excellent though.
We recently took a look at the top hundred PlayStation four titles as ranked by play time, and we're expecting almost all of them to be playable at launch on PlayStation five.
