More Cell Processor Details And First Pictures

slashflood writes "After reading two articles on slashdot about the Cell architecture and another one that criticizes the extensive roundup of the STI patents, I found the first pictures of the Cell core. It seems that at least some predictions were true. Seeing is believing." mtgarden points to this ZDNet article which says that the "first version of the chip will run at speeds faster than 4GHz. Engineers were vague on how much faster, but reports from design partners say 4.6GHz is likely. By comparison, the fastest current Pentium PC processor tops out at 3.8GHz." (More below.)

Hack Jandy writes "Anand Shimpi has some details about the upcoming Cell processor (PS3) in his personal blog. According to Anand, "Rambus announced that the new Cell processor uses both Rambus XDR memory and their FlexIO processor bus. Because Rambus designed the interface for both the memory controller(s) and the processor interface, the vast majority of signaling pins are using Rambus interfaces - a total of 90% according to Rambus." Hasn't Rambus been showing up a lot again recently? The fact that Cell uses XDR has been widely speculated, but the fact that it will also use the Rambus bus signalling is something completely new."

Comments

Speed isn't everything

[leathered]

While 4.6 GHz sounds impressive, I thought we were getting away from the notion that clock speed = performance. The Pentium 4 killed off clock speed comparisons.

I must admit the specs are impressive, but show me the benchmarks!

Re:Speed isn't everything

[jc42]

I thought we were getting away from the notion that clock speed = performance.

Actually, there's a good use for such comparisons: It tells you that the writer is clueless.

I'd already read enough about the Cell to know that it's more like the PowerPC than it is like an Intel cpu. So, when I read the comparison of its supposed speed and a Pentium's, I immediately knew that the writer hadn't a clue.

Any info around about benchmarks? Those can be misleading, too, in the hands of the wrong marketer. But with enough of them, it's a lot more likely that you can glean some actual speed info.

Re:Speed isn't everything

[chrysrobyn]

While 4.6 GHz sounds impressive, I thought we were getting away from the notion that clock speed = performance. The Pentium 4 killed off clock speed comparisons.

Nobody is claiming that clock speed always equals performance, but think about it this way -- say you have data coming in at 10 GB/s. You could either have 8 wires (and buffers and processing) running at 10 GHz, 16 wires (etc.) running at 5GHz, 32 wires at 2.5GHz (etc.), you get the idea. If the Cell architecture processes data at 4GHz, the only thing we can be pretty certain of is that the pipeline is very deep. The benchmarks you want to see will very likely be very impressive. Perhaps the speed was partially dictated by wire density and transistor sizing?

Real world, though, what does this mean? This chip is due to be a game machine. Game workloads are, for the most part, very predictable. You process an entire screen of graphics in a very similar manner every time. This means that if you get the prediction models (and compiler hints) right, your actual performance will be very high. The same supposition could be made for encryption or any other bulk vector processing, with obvious strengths according to the instruction set of the processor. General workloads, however, do not do very well with deep pipelines. They tend to prefer less of a pipeline and less of a branch mispredict penalty. Cell will be great at its intended market, but you don't use a 4+GHz chip with over half the area (guessing, looking at the pictures) tuned for vector math (the APUs have been called SIMD) to take over the PC. For that, we will still have multicore x86 and PPC chips to dream about.

Re:Speed isn't everything

[Prehensile Interacti]

Actually this is initially designed for Sony's PlayStation 3.

Games are inherantly very parallel.

• Loads of chracters
• Loads of animations
• Loads of discreet AIs
• Loads of polygons
• Loads of lights
• Loads of sounds

The amount of interaction between individual entities in a game world is very low, and most of a game frame is spent shovelling data asafp to the screen. Once you are in your shovelling phase, then the parallelism will be completely maxed out.

There are some of the smartest programmers around making games. Those who got over the initial pain of the Ps2's 3 core architecture should find it relatively easy to scale up. What is most exciting this time is that the 8 cores appear to be identical, meaning that there will be less restrictions about what you use each for.

The o.p. was scoffing at a 4.6Ghz spec. Whilst maybe overstating the Cell a little with my reply, the escense is that he was an order of magnitude out in his understanding.

Hot

[porksickle]

I don't think the final PS3 part will be clocked much higher than 3.5GHz. Otherwise it would probably involve downclocking parts of the CPU to maintain a sane thermal profile, thus making overall performance rather unpredictable. This would especially impact games, where it's all about sustainable framerates at 100% CPU utilization.

Re:Rambus kills cell...

[ErikTheRed]

So this will just be like the last time Rambus had their hooks into a product, it will die a very expensive and slow death.

We'll see. IBM has historically been very smart (and sometimes downright ruthless) when it comes intellectual property issues. Their IP attorneys aren't referred to as "The Nazgul" for nothing...

The Sony hype machine strikes again

[Laconian]

Remember how the Emotion Engine worked us all into a lather five years ago? And when it came out, it was just merely competitive with contemporary processors? Sony is great at churning out nerd fetish tech, but they have a terrible track record of living up to their promises. Let's hope it's different this time.

Re:by comparison...

[rco3]

what does your oscilloscope need a D/A converter for? Do you mean an A/D converter? And why 1,024 bits? That's 128 channels worth of 8-bit A/D.

What scope is this?

Re:Cell

[radixvir]

With how cheap they arespeculated to be

Please explain why you think this will be cheap. Everything i see points to a very expensive chip. With rambus memory technology, an ibm design, and the fact that it's brand new, I dont know where you are coming up with the idea this thing will be cheap. Not to mention everyone thought the Itanium would spell death for x86, but that went nowhere.

Re:I don't get it

[gbulmash]

This seems good, but what exactly can I do with a cell processor other than play games with better graphics? It seems like the vast majority of people don't use even half of the power their computers have today, and if there are bottlenecks in todays computers it is because of RAM and the OS and not because of the CPU. Other then games, when will I be able to do other than maybe look for aliens faster.

"If you build it, he will come."

If you create a machine so powerful that there's nothing that fully utilizes its capacities, that merely spurs all sorts of geeks to dream about how they can push that machine to its limits, then overclock it, then put it all in a case made of Legos.

- Greg

Re:Cell

[Wesley Felter]

The feature sizes are 90 nm and the wafers are 300 mm in diameter.

Unlikely.

[katharsis83]

"plan to recoup their R&D expenses largely from other consumer multimedia devices and NOT from selling Cell processors or Cell processor based computers, meaning they will be surprisingly inexpensive. Yeah!!!"

However, from the press release:
Prototype die size of 221mm2

When it comes to chip manufacturing, the cost of a chip is basically a direct function of the area. A 221 mm^2 chip size is pretty damn big; this thing isn't going to be cheap. Even considering IBM's extensive fabrication experience, Sony will probably have to sell this at a significant loss to make the PS3 palatable to gamers.

Granted, this is a prototype, so they can probably shrink it further by production, but it still won't be something cheap. Don't count on being able to buy these cheaply to make your own parallel supercomputer.

Re:Cell

[sleepingsquirrel]

300mm is the size of the silicon wafer, not the size of anything on the chip.

Dont jump the gun...

[SteveXE]

Before everyone starts having digital orgasms over this chip we should take a sit back and watch approach. This all sounds amazing on paper as did PS2 and look how that turned out in terms of hardware power.

We have no idea if developers will be able to easily adapt and get any real performance out of this thing above and beyond what they get from CPU's now. Almost nobody uses the vector units in PS2, who says they will start now? In terms of just gaming I wanna see some games and examples of this thing running in real time before i start taking my wallet out of my pocket, Sony burned me last time with underpowered bug ridden hardware, ill be damned if i let them do it again.

Re:ANY ___FACTS___ AT ALL??

[be-fan]

Did you RTFA? From the second article:

Die size: 221mm^2
Transistor count: 234m
SPE Size: 2.5x5.81mm
SPE Interconnect: 4x128bit ring bus
SPE local memory: 256KB
SPE decode rate: 2 insns/cycle
SPE resources: 7 execution units (unspecified type)

They also mention the core voltage of the CPU (1.3V), the fact that the memory has been tested to 5.4GHz, detail the temperature monitoring scheme, and the fact that the SPEs are in-order chips. This is all new information.

Re:Cell

[nokiator]

As usual, media is making a bigger deal out of this than what it really is worth. After looking at the details in the articles linked above, Cell looks to me like a combination of two well known technologies: SIMD units integrated with a microprocessor and MIMD geometry engines that is used in all modern GPUs. STI team must have figured out that moving the geometry engines from the graphics coprocessor to the main CPU may provide performance benefits in terms of processing 3D data structures. As for the 4+ GHz clock speed, this is more likely the pipeline clock speed for the SPEs and the embedded PPC core on this device would probably run from a much slower (2.4GHz?) clock. Current Intel P4 processors use 1.5X core clock in some parts of the floating point unit, so you should consider a 3.8GHz P4 to be a "5.7GHz" chip to make a fair comparison to the speculated clock speeds for the cell chip.

Re:Cell Processor enhances cross-platform software

[action789]

I'd be far more worried about malcode (virii, worms, etc) taking hold in the cross-platform evironment the parent mentions than worrying about games.

Re:Cell

[Anonymous Coward]

Depends on how much it costs Sony to manufacture these chips on their own 300mm wafer production lines.

The 90nm size is quite large, maybe it would cost around $100 a chip to make, making a PS3 around $600 to make. However that is if Sony were to release the PS3 this year. Because it is all in-house, it'll probably cost less per chip to make a Cell. When it hits 65nm, it'll cost even less because the chip is half the size (which actually means less than half the cost to make because yield increases). Then you don't have packaging costs, etc, so that is even less. Maybe Sony will get the cost per Cell down to $50 by the time of release for the PS3, meaning a manufacturing cost of $400.

Absorbing a $100 per console isn't too bad, so it could probably be sold for $299 by late 2006.

Re:PS3

[AssFace]

The GHz figures mean nothing at all in terms of performance expectations unless you are comparing within the same processor family.

4GHz cell != 4GHz P4 != 4GHz Opteron != 4GHz G5

Re:Missing the point

[X]

I'm not sure that this makes for the "extreme goodness" that people are envisioning. It should be truly awesome for SIMD type operations, such as video encoding/decoding and 3D rendering. But I don't see much of a break through here in more general compute tasks. If you've worked with an Itanium, you know the parallelism limits you hit with VLIW instruction sets and having a bunch of VLIW processing units is just going to make it worse.

All in all, this thing strikes me as more of a next-generation DSP rather than a next-generation CPU, with a lot of hype thrown in (btw, the are apparently now called "synergistic processor elements" instead of "attached processing units" ;-).

Re:Rambus kills cell...

[WasterDave]

So this will just be like the last time Rambus had their hooks into a product, it will die a very expensive and slow death.

You mean like the PS2 did (given that is uses RDRAM)?

Dave

Re:Cell

[Glonoinha]

Sure, it doesn't serve up a site or anything

Amazing how fast those i386 processors were at doing absolutely nothing at all.
Assign your Linux box a task or two and all of a sudden faster CPU's become appealing.

My C=64 was a bad motherfucker, right up until the point I wanted to do some serious number crunching on it (or play games.) The minute I decide that there's more to life than interacting with the operating system on an 80x25 character wide CUI ... corporate grade relational databases serving up data to a few dozen concurrent users for example, or multivariant calculus and diff/equations - and I'm looking for all the horsepower I can get.

Plus I bet it plays a mean game of Doom III.

Re:Conspiracy Theory

[Queer Boy]

So my speculation is that it is possible that Apple intends to build a new Mac aimed at the gaming market that will be compatible and play Sony's PS3 games- Apple in turn could publish games for the PS3.

Or it's possible that Apple is writing the OS for the PlayStation3.

The overwhelming majority of people do not play games on computers nor do they want to. The living room is where entertainment is king. The sheer horde of developers for consoles compared to the paltry handful for PCs should be a clue as to where the money is.

Don't give me all that jibber jabber

[glrotate]

as Mr. T would say.

How about some actual SPECint and SPECfp?

Oh, nothing like that was released? Hmm. makes you wonder. Sort of like the Itanium flop where the excuse, going on for about 10 years now, is that the compiler isn't quite optimised yet.

Any nerd over 15 ought to have heard far to many claims of "revolutionary cpu design" to know better.

Re:Cell

[Fulcrum of Evil]

Any links to back that up? The only confirmed unit loss consoles I know of are the Xbox and the dreamcast. Everything else (to my knowledge) has been profitable. I looked around and the only sites that are claiming that the PSP is sold at a loss are 1up.com and some people on the chat forums. I also found a bunch of posts claiming that Sony expects to not sell the hardware at a loss. Perhaps the initial allocation was sold cheap to create buzz?

Re:Well, cause Intel is a failure

[Sycraft-fu]

Hey man, if $34 Billion in revenue is getting your butt spanked, then line me up and get the paddle.

As for graphics, those have been a huge success, to the point that nVidia and ATi began copying the idea. Intel's integrated chipsets are a huge hit with business. They keep costs and space down, and high performance grapihcs aren't necessary for office work. The integrated low-end graphics chip is getting to be quite popular.

Networking would be another huge non-processor area that they excell in. If you ask me what kind of NIC I want in a server, Windows, Linux, BSD, whatever, the answer is Intel. Nobody else I know makes cards of the same quality. 3com used to, but not anymore.

Now the x86-64 thing is an interesting one to pick on, because the reverse is true. AMD was being the uninnovative one. They decided that innovation, in this case, was unnecessary and counter productive. They decided to just whack on 64-bit extensions to the x86 architecture, as was done with the 32-bit conversion years ago, and call it good. It offered nothing new in terms of ISA, but that meant backward compatibility.

Intel tried to be radical. EPIC is a neat idea that's been messed with for years and never made practical. You have the compiler do all the work of deciding what runs in parallel, rather than the chip. Makes for helaciously complex assembly, but that's ok, you just need a good compiler, and Intel makes the best.

Well, total non-starter in the desktop market, that's gone to x86-64 and it's not changing. However seems to be working in the high end computation market. We just got in 2 racks of SGI Itanium coputers for one of the research labs. From what I hear, they are badass number crunchers.

Now if you want to talk some major failures, let's have a look at AMD's motherboard situation. When the Athlon came out it was abysmal. AMD couldn't produce a reasonable chipset to support their own processors. It was slow and incomplete, and couldn't deal with basics like AGP 2x. VIA had a full featured chipset, that was full of bugs and couldn't handle hardware like the GeForce in many configurations. ACPI problems plauged all boards.

Now the point here isn't to try and say Intel's better than AMD. The point is, both companies have hits and misses. Some products can be both a hit in one way, and a miss in another. However there's a lot of fanboyism about AMD and hate towards Intel and its not productive.

You should pick your platform based off of informed choices about what performs better for you, and gives you that performance at the best price. If you find yourself having to justify it by attacking the other company, you probably made it for the wrong reasons.

This goes extra for doublespeak like hating on Intel for focusing on MHz, then hating on them again when someone else does so.

Re:Cell

[Breakfast Pants]

Your geforce does massive parrellel computations. At 400Mhz it is getting a lot done. You don't quite understand Mhz. Current Athlons are way under the clock rate of P4's yet offer similar performance. A P4's FP unit runs at more than 4Ghz. Modern DSP's run above 10Ghz. Clock rate is not the only factor in a chip. You say you know they aren't exactly comparable... you are completely right, except replace "exactly" with "even a little bit".

Cell is not an x86 competitor.

[flaming-opus]

It is a radeon/geforce competitor. Or something like that.

The cell processor is only really fast when the spus are in use, which means 32-bit non-branching floating-point arithmatic. For anything involving integer math, flow control, or uneven memory access, the SPUs defer to the main processor. I'm sure IBM put a decent processor in there, but it doesn't sound like it's anything revolutionary, and there's only the one.

What does this get you? -- A processor that is really good at decoding mpeg, rendering graphics, maybe approximating the physics of flying dragons. It is not a fast general purpose processor. Operating systems, word processors, databases, these are all integer tasks, and much more-so they are branch tasks. Scientific computation - this requires double-precision floating point. Photoshop is about the only piece of non-multimedia software that might be able to take advantage of this.

The end result is that this will likely be a great chip for set-top boxes of all sorts, maybe even for video-editing workstations. A G5/pentium replacement it isn't; that's a different ball game.

Re:Cell's PowerPC core is in-order not out-of-orde

[EvilTwinSkippy]

The PowerPC instructions core is simply to provide a way to leverage existing compilers against this new architecture. Sony learned, the hard way, that developers don't want to hear about a quirky new instruction set.

I hear you though. The Power5 is designed to handle large multi-process loads. This new Cell architecture, or at least this particular Cell chip, is designed for real time processing of large piles of data.

I'm not reliving computer architecture class... I'm not reliving computer architecture class... (open's eyes) ... Whew