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The Steam Deck is Awesome at 128bit 88GB/s bandwidth

ToTTenTranz

Banned
EDIT:
- The rumors were wrong. The memory controller is 128bit wide.
- The Steam Deck is Awesome at 88GB/s.
- Sorry for the false concerns.


And why is this important?
Because that's extremely low and the iGPU is probably going to be bottlenecked the whole time, eventually making it perform worse than the handhelds that are already in the market.

Valve is only saying they're using LPDDR5 5500MT/s but they're not disclosing the bus width... and I'm reading some sources claiming that the bus is actually 64bit wide.
So at 5500MT/s and a 64bit (8byte) bus, what this means in practice is that the memory bandwidth will be only 5.5*8 = 44GB/s, shared between CPU cores and iGPU.

For example, the Series S has 224GB/s and the PS5 has 448GB/s. The AYA NEO uses LPDDR4X 4266MT/s but with a 128bit bus, meaning it gets 68GB/s, and so do the Intel Tiger Lake handhelds like the OneXPlayer and GPD Win 3.

It's especially bad considering that Zen2 APUs have very little L3 cache (probably only 4MB L3 in Steam Deck), meaning it needs to access the main RAM quite often, which takes bandwidth away from the GPU. In Intel's Tiger Lake case, it has 12MB L3 that the GPU can access too.
Back in 2013 Sony estimated that the PS4's Jaguar CPU cores would take around 20GB/s, and I don't see why the 4-core Zen2 would use less. That would mean the GPU will struggle with some 24GB/s available bandwidth, which is ten times less the bandwidth of a Radeon RX 5500.

Still, I hope the info I'm getting is wrong, or if the specs are missing something like Infinity Cache of sorts.

I'm saying this to level the performance expectations of Steam Deck. If the 44 GB/s bandwidth number is true, it's likely to perform closer to a 1TFLOPs console than a 2 TFLOPs one.
 
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Astral Dog

Member
Its not magic Deck is just a handheld device, i don't think its meant to catch up with the Series and PS5 at this time.

Steam Deck should be able to comfortably play all your last gen games at 800p with good settings, if you need a real 'next gen' console better buy a PS5 or Series X
 
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Hugare

Member
Jesus fucking christ, of course its not gonna be Series S in terms of power

Expect a portable PS4, people.

That would still be good enough and more powerful than any other handheld on the market

People expecting a portable next gen console for $400 are delusional
 
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ethomaz

Banned
The Valve site says dual-channel.
LPDDR5 channel is 16bits (DDR5 is 32bits per channel).
So unless they used the wrong term in the site it will be 22GB/s.

Yea either 22GB/s or 44GB/s is pretty low.

PS4 weaker APU had 176GB/s for 1080p.
A better the even weaker Xbox One had 68GB/s and due that have a hard time 1080p focusing early in 720p resolution that late got better due MS having to use the ESRAM to cover up the low bandwidth.

The Ryzen 7 5800H in most implementations uses a 68GB/s bus but in test it was the main bootleneck of the systems… increasing the bandwidth increased a lot the performance of the APU.
 
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silent head

Member
And why is this important?
Because that's extremely low and the iGPU is probably going to be bottlenecked the whole time, eventually making it perform worse than the handhelds that are already in the market.

Valve is only saying they're using LPDDR5 5500MT/s but they're not disclosing the bus width... and I'm reading some sources claiming that the bus is actually 64bit wide.
So at 5500MT/s and a 64bit (8byte) bus, what this means in practice is that the memory bandwidth will be only 5.5*8 = 44GB/s, shared between CPU cores and iGPU.

For example, the Series S has 224GB/s and the PS5 has 448GB/s. The AYA NEO uses LPDDR4X 4266MT/s but with a 128bit bus, meaning it gets 68GB/s, and so do the Intel Tiger Lake handhelds like the OneXPlayer and GPD Win 3.

It's especially bad considering that Zen2 APUs have very little L3 cache (probably only 4MB L3 in Steam Deck), meaning it needs to access the main RAM quite often, which takes bandwidth away from the GPU. In Intel's Tiger Lake case, it has 12MB L3 that the GPU can access too.
Back in 2013 Sony estimated that the PS4's Jaguar CPU cores would take around 20GB/s, and I don't see why the 4-core Zen2 would use less. That would mean the GPU will struggle with some 24GB/s available bandwidth, which is ten times less the bandwidth of a Radeon RX 5500.

Still, I hope the info I'm getting is wrong, or if the specs are missing something like Infinity Cache of sorts.

I'm saying this to level the performance expectations of Steam Deck. If the 44 GB/s bandwidth number is true, it's likely to perform closer to a 1TFLOPs console than a 2 TFLOPs one.
The Valve site says dual-channel.
LPDDR5 channel is 16bits (DDR5 is 32bits per channel).
So unless they used the wrong term in the site it will be 22GB/s.

Yea either 22GB/s or 44GB/s is pretty low.

PS4 weaker APU had 176GB/s for 1080p.
A better the even weaker Xbox One had 68GB/s and due that have a hard time 1080p focusing early in 720p resolution that late got better due MS having to use the ESRAM to cover up the low bandwidth.

Samsung’s latest 16 GB LPDDR5 package consists of eight 12 Gb chips and four 8 Gb chips featuring a 5500 MT/s data transfer rate that can provide bandwidth of up to 44 GB/s.
 
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Jesus fucking christ, of course its not gonna be Series S in terms of power

Expect a portable PS4, people.

That would still be good enough and more powerful than any other handheld on the market

People expecting a portable next gen console for $400 are delusional

The PS4 still has close to 4 times the memory bandwidth.

If the OP is true, this will cripple the performance of the device to a point where I wonder why they even bothered with such a large GPU/CPU. They could have slashed both in half and still performed at practically the same level in games.

Also, all those hoping for great NVME SSD performance with DirectStorage, the dream is officially dead. Without the dedicated coprocessors to help with compression/decompression and IO like the PS5, the CPU will have to work multiple times as hard to pick up the slack here, and with this level of memory bandwidth available... well... good luck with that.
 

Hugare

Member
The PS4 still has close to 4 times the memory bandwidth.

If the OP is true, this will cripple the performance of the device to a point where I wonder why they even bothered with such a large GPU/CPU. They could have slashed both in half and still performed at practically the same level in games.

Also, all those hoping for great NVME SSD performance with DirectStorage, the dream is officially dead. Without the dedicated coprocessors to help with compression/decompression and IO like the PS5, the CPU will have to work multiple times as hard to pick up the slack here, and with this level of memory bandwidth available... well... good luck with that.
People are jumping to conclusions since they dont even know the bus width yet

But one thing is certain: it can run Control and Death Stranding (IGN Hands On)

Freaking Control

So it will do fine
 
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OLED switch is 350, Deck is $400, ipso facto, $50 difference for twice the performance. Call it $100 difference if you'd like.

Here’s Why the Nintendo Switch (OLED Model) Price Is $50 More Expensive - IGN

And this is $399.

Yeah... of course... as if the 64GB Steamdeck version has any value. Get real.

That's nowhere near enough storage. It might as well not exist. Practically nobody is gonna buy it. It's the 20GB PS3 all over again.
 
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kingfey

Banned
720p system. Its for handle held. Not an actual gaming system. This system is not gonna give you 4k to 8k view. Gamers are sometimes too picky. This is why we cant enjoy small things.
 

SlimySnake

Flashless at the Golden Globes
The PS4 still has close to 4 times the memory bandwidth.

If the OP is true, this will cripple the performance of the device to a point where I wonder why they even bothered with such a large GPU/CPU. They could have slashed both in half and still performed at practically the same level in games.

Also, all those hoping for great NVME SSD performance with DirectStorage, the dream is officially dead. Without the dedicated coprocessors to help with compression/decompression and IO like the PS5, the CPU will have to work multiple times as hard to pick up the slack here, and with this level of memory bandwidth available... well... good luck with that.
It's not a next gen machine, but IGN went hands on with it and were able to play Control, Death stranding, Doom Eternal and Star Wars Fallen order at 'smooth' framerates. I am guessing 30 fps.

You can find footage of games being played on it on their website and in several of the previews. So it seems it can run PS4 games at medium to high settings, but PS5 games are out of the question. Which was probably a given after their decision to not include an SSD in the base SKU.
 
Jesus fucking christ, of course its not gonna be Series S in terms of power

Expect a portable PS4, people.

That would still be good enough and more powerful than any other handheld on the market

People expecting a portable next gen console for $400 are delusional
It's not jumping to conclusions. Valve have already stated it's 16GB LPDDR5 with 5500MT/s. There's only so many ways something like that can be configured reasonably in a portable device form factor. Unless you think it's gonna be 16x 1GB chips?

There's also this, which is as good as a confirmation:

Samsung’s latest 16 GB LPDDR5 package consists of eight 12 Gb chips and four 8 Gb chips featuring a 5500 MT/s data transfer rate that can provide bandwidth of up to 44 GB/s.
 

ToTTenTranz

Banned
Jesus fucking christ, of course its not gonna be Series S in terms of power
No one suggested that.

Expect a portable PS4, people.
The PS4 has a 1.8TFLOPs GPU and 176 GB/s bandwidth. Take away 20GB/s for the Jaguars and the GPU gets 156 GB/s.
The Steam Deck, if these rumors are true, has a 1.6 TFLOPs GPU and 44 GB/s bandwidth. Take away 20GB/s for the Zen2 and the GPU gets 24 GB/s.


People are jumping to conclusions since they dont even know the bus width yet

But one thing is certain: it can run Control and Death Stranding (IGN Hands On)

Freaking Control

So it will do fine
You saw cam footage of the console running those games, at undisclosed resolution and undisclosed settings and undisclosed framerate.
 

kingfey

Banned
People are jumping to conclusions since they dont even know the bus width yet

But one thing is certain: it can run Control and Death Stranding (IGN Hands On)

Freaking Control

So it will do fine
The switch had to use the cloud to run the game. Valve steam can also run fallen order at high setting.
 

Md Ray

Member
This was my concern too. I'm puzzled that people like Durante quickly jumped into comparing this with Series X based on just TFLOPs numbers without taking other factors into consideration like the bandwidth, SoC power limits, and whatnot.

Expect a portable PS4, people.
Jake Gyllenhaal No GIF
 
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CamHostage

Member
Its not magic Deck is just a handheld device, i don't think its meant to catch up with the Series and PS5 at this time.

Steam Deck should be able to comfortably play all your last gen games at 800p, if you need a real 'next gen' console better buy a PS5 or Series X

So no, it's not meant to compete on quality terms with XBS or PS5. Performance comparisons end up being a little silly, holding it to those standards and not as a portable device in a small and exciting class of its own.

However, I think it is important to consider the level of software it can (or potentially cannot) play. We're in a slow-but-moving push to next-generation gaming technology, and right now Steam Deck is selling itself as powerful enough to play your PC games today, but as more titles become the PC games of tomorrow, there will be a hard and ever-widening line of games Deck cannot play. It's not about "power", it's about "ability".

Generally, though, there are tons of games on Steam/PC to play (especially if you are into indies) and especially for a handheld, it looks like it has the juice to do a lot of work. So, it's smart to understand the specs and define expectations, yet it's possible to understand its limits and admire its abilities at the same time.
 
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It might be 64-bits wide, but we don't know for sure. They are likely using soldered RAM chips; I don't know if 4 GB capacity modules exist yet for LP-DDR5 but if so that could increase them soldering them to the board as 4x 32-bit chips and that essentially doubles the bus to 128-bit and clears up any bandwidth issues speculated on in your OP.

Intel has several DG1-based video cards with soldered LP-DDR4/LP-DDR4X memory arranged in 128-bit bus interfaces, although since they are LP-DDR4/LP-DDR4X their bandwidths are lower. In any case, it's evidence that they can arrange the LPDDR in 128-bit bus configuration and I would think Valve, building Steam Deck primarily for gaming, would have taken this into account and gone for a 128-bit bus interface for their memory.

It's actually less likely that it has Infinity Cache; that seems to be reserved for larger RDNA2-based GPUs, probably not even intended for APUs (at least for ones with RDNA2).

The PS4 has a 1.8TFLOPs GPU and 176 GB/s bandwidth. Take away 20GB/s for the Jaguars and the GPU gets 156 GB/s.
The Steam Deck, if these rumors are true, has a 1.6 TFLOPs GPU and 44 GB/s bandwidth. Take away 20GB/s for the Zen2 and the GPU gets 24 GB/s.

Which is why it seems very unlikely Valve would go with a 64-bit bus interface for a device like this in the first place. It is also intended as a sort of NUC-style mini PC via the dock. Nothing has been said on if the RAM is upgradable so it is likely soldered, and crippling the Steam Deck to 64-bit interface with bandwidths you mention would destroy its prospects before it even launched.

Just can't see Valve making that type of engineering/design blunder at such a fundamental level. I think 128-bit interface is present and that should give them enough bandwidth for the GPU even with the CPU using some of it.

It's not jumping to conclusions. Valve have already stated it's 16GB LPDDR5 with 5500MT/s. There's only so many ways something like that can be configured reasonably in a portable device form factor. Unless you think it's gonna be 16x 1GB chips?

There's also this, which is as good as a confirmation:

Interesting; are Samsung the only ones who manufacture LP-DDR5? What if Valve are using the newer 6400 MT/s package? Regardless of package speed, what if they are using smaller 8 GB packages but two of them?

The one in the linked article appears to be 32-bit.
 
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ToTTenTranz

Banned
Samsung’s latest 16 GB LPDDR5 package consists of eight 12 Gb chips and four 8 Gb chips featuring a 5500 MT/s data transfer rate that can provide bandwidth of up to 44 GB/s.
That would mean not all memory is available at the same 44GB/s.
I don't think that's what they're using, because at the moment the only solution that Samsung has on production in their website are 48Gb / 6GB chips, and that news is 17 months old.
 

Rikku-X

Member
The PS4 still has close to 4 times the memory bandwidth.

If the OP is true, this will cripple the performance of the device to a point where I wonder why they even bothered with such a large GPU/CPU. They could have slashed both in half and still performed at practically the same level in games.

Also, all those hoping for great NVME SSD performance with DirectStorage, the dream is officially dead. Without the dedicated coprocessors to help with compression/decompression and IO like the PS5, the CPU will have to work multiple times as hard to pick up the slack here, and with this level of memory bandwidth available... well... good luck with that.
The proof is in the pudding, the steam deck is already running Control at high settings at 60fps, even the ps5 Pro is not doing that.
 

spons

Gold Member
I'm gonna stick my head in the sand and pretend it's fine. Just don't expect any miracles. 720p/30FPS is my target and probably this device's one as well.
 

Fredrik

Member
You saw cam footage of the console running those games, at undisclosed resolution and undisclosed settings and undisclosed framerate.
We can see that it looks fine on that screen, we can assume it’s running at 720p since Control doesn’t let you go lower unless it’s 4:3, it runs smooth according to IGN, enough to get them to forget it’s not a desktop PC when docked, assumably 30fps or higher.
 
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Errr... a 1TB SD card is over $200.

So with that we're right back to where we started from, i.e. my argument that you're paying $600+ for the device with reasonable storage.
That wasn’t your argument. You said who’s paying 600+ for it it. Answer: The bulk are not as the 256 model has more than reasonable storage without an SD. The SD slot is a nice to have, but by no means a requirement. The same 700,000 people that are playing Witcher 3 on the Switch would relish playing it on a device that is twice as strong for ~$100 more.
 

ethomaz

Banned
Then i would not bother with sd card. Id just get an normal usb ssd .
I believe most users doesn't take that option because it should break the portable ideia.
The device is already big and you will have to hold it and a USB HDD in the hands to play outside home... the SD cards is more useful for a portable device.

But hey there are people that keep holding the cellphone + powerbank in the hand all the time outside home lol
 
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sunnysideup

Banned
I believe most users doesn't take that option because it should break the portable ideia.
The device is already big and you will have to hold it and a USB HDD in the hands to play outside home... the SD cards is more useful for a portable device.
i have an samsung 2tb ssd its the size of a credit card. Only a bit thicker. With an adapted usb cable and some sort of tape. I doubt you would even notice it. Im sure some alibaba company will make some sort of usb dongle thing that fits the console.

Aint no way im using an sd card.
 
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Sentenza

Member
Do you realize that several MORE HIGHLY PRICED alternatives in the PC handheld scene like the GPD WIN 3 (999 dollars as starting price) use LPDDR4, right?

 
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