Why would playstation3 cell processor not work well as gpu?

[her34]

Sony has historically created their own chips for their videogame systems (ps1, ps2, psp). Supposedly ps3 was to be the same way (using 2 cell processors to function as cpu and gpu) but when they were able to test out a 2 cell machine, performance wasn't up to par so they scrambled to get an off the shelf chip (7800GTX) and slightly modified it.

Technically speaking, what makes the 7800gtx more competitive than cell?

 

[BladeVenom]

A GPU offers a lot of parallel processing specifically made for graphics. http://www.anandtech.com/video/showdoc.aspx?i=2451&p=2

 

[QuixoticOne]

I think beyond3d.com is your resource for the technical level detail as to what the story with the PS3 and Cell and their GPU merits / problems are/were. Short of a PS3 game coding specific site that site has the best detailed architectural review threads I've seen.

 

[TuxDave]

Perhaps they have more fixed function hardware like texture samplers?

 

[tcsenter]

Originally posted by: her34
Technically speaking, what makes the 7800gtx more competitive than cell?

Other than Cell takes a huge performance hit when doing double-precision floating point, there is no reason why Cell can't be very good for graphics. Its just that Cell is a bitch to code for and graphics SDK/API/libraries were not yet mature enough to really exploit Cell's capabilities for conventional GPU work. Even if it had been much better, it would still result in increased coding difficulty and steeper learning curve for game developers, which any console maker must be sensitive to.

Cell is an eff'n beast when the code is written explicitly for it. e.g. GPGPU apps for PS3 like F@H are done almost entirely using the Cell, not the GPU.

 

[CTho9305]

Cell is pretty slow compared to a GPU. At 4 GHz, a Cell processor would be capable of ~256 single-precision GFLOPs theoretically, and the PS3 was available in November 2006. The GeForce 8800 series cards are all capable of over 200 GFLOPS; the GTX was available in late 2006 and was capable of >300 GFLOPS. Cell loses in terms of theoretical performance right off the bat. However, it gets worse, because there is a lot of specialized logic in GPUs to accelerate things important to graphics (e.g. dedicated texture samplers, which drastically improve texture sampling performance when you're using things like anisotropic filtering). I don't know if the texture samplers' computational power (which is useless for most general-purpose applications) is counted in THG's numbers.

 

[Cogman]

I have no idea what sony was trying to pull with the cell processor. Yes it makes a good super-computer processor but definitely not a good general purpose processor, or even a good graphics processor. (and really, there are now better choices for supercomputer processors now). They essentially doomed the PS3 from the beginning by saddling it with a processor that nobody could code for and an API that nobody could understand. All for the bragging rights to say "Well, we have 8 processors! What do you have, 2?"

So now you have this platform, with no really good games to start out with, and few games being planned for release. Nintendo released the Wii which was, you know, FUN to play. and Microsoft the 360 which gain a lot more developer support and hence more games from the git-go. But hey, you could own a black box that can play HD movies, and... Uh... Fold, yeah thats good.

 

[soccerballtux]

Originally posted by: Cogman
I have no idea what sony was trying to pull with the cell processor. Yes it makes a good super-computer processor but definitely not a good general purpose processor, or even a good graphics processor. (and really, there are now better choices for supercomputer processors now). They essentially doomed the PS3 from the beginning by saddling it with a processor that nobody could code for and an API that nobody could understand. All for the bragging rights to say "Well, we have 8 processors! What do you have, 2?"

So now you have this platform, with no really good games to start out with, and few games being planned for release. Nintendo released the Wii which was, you know, FUN to play. and Microsoft the 360 which gain a lot more developer support and hence more games from the git-go. But hey, you could own a black box that can play HD movies, and... Uh... Fold, yeah thats good.

I understood they did it for the Blu-Ray decoding, the SPEs are perfect for that. I wonder if graphics card accelerated video hadn't been conceived when they were designing the Cell.

 

[dinkumthinkum]

Originally posted by: tcsenter

Originally posted by: her34
Technically speaking, what makes the 7800gtx more competitive than cell?

Other than Cell takes a huge performance hit when doing double-precision floating point,

NB: Most GPUs are geared towards single-precision floating point calculations, also.

 

[BladeVenom]

Originally posted by: Cogman
I have no idea what sony was trying to pull with the cell processor. Yes it makes a good super-computer processor but definitely not a good general purpose processor, or even a good graphics processor. (and really, there are now better choices for supercomputer processors now). They essentially doomed the PS3 from the beginning by saddling it with a processor that nobody could code for and an API that nobody could understand. All for the bragging rights to say "Well, we have 8 processors! What do you have, 2?"

So now you have this platform, with no really good games to start out with, and few games being planned for release. Nintendo released the Wii which was, you know, FUN to play. and Microsoft the 360 which gain a lot more developer support and hence more games from the git-go. But hey, you could own a black box that can play HD movies, and... Uh... Fold, yeah thats good.

I think they went with it for marketing purposes. It certainly wasn't the CPU that game developers wanted.

 

[destrekor]

Originally posted by: BladeVenom

Originally posted by: Cogman
I have no idea what sony was trying to pull with the cell processor. Yes it makes a good super-computer processor but definitely not a good general purpose processor, or even a good graphics processor. (and really, there are now better choices for supercomputer processors now). They essentially doomed the PS3 from the beginning by saddling it with a processor that nobody could code for and an API that nobody could understand. All for the bragging rights to say "Well, we have 8 processors! What do you have, 2?"

So now you have this platform, with no really good games to start out with, and few games being planned for release. Nintendo released the Wii which was, you know, FUN to play. and Microsoft the 360 which gain a lot more developer support and hence more games from the git-go. But hey, you could own a black box that can play HD movies, and... Uh... Fold, yeah thats good.

I think they went with it for marketing purposes. It certainly wasn't the CPU that game developers wanted.

Well, Sony was really just working in a style they always have when it comes to game consoles, and is exactly what game consoles have always been.
Microsoft, being a software company, decided it would easiest to get into the gaming market if they basically built a customized PC with off the shelf PC tech. They didn't really move away from that at all with the Xbox 360, just now it had more console-customized tech.
I expect Microsoft will continue down that road with the CPU, but is going to get more advanced with the rest of the architecture, while Sony might be forced to simplify the architecture just out of developer demand.
Sony, Toshiba, and IBM worked on the Cell, for use in the PS3.
Sony and Toshiba built the Emotion Engine, a MIPS-based CPU, used in the PS2.
And Sony used a MIPS CPU built for them for the PS1.

It's very likely Sony will use a chip based on the Cell architecture... it may deviate enough from the original architecture of the PS3's Cell to be different and more powerful, but still based on the same technology, with the concept being a POWER-based PPE, and multiple SPEs.
A potential upgrade path could be a multi-core PPE element, and more powerful SPE elements. The current PPE is dual-threaded. Maybe due to die size restrictions the PPE may not be able to be made into a multi-core element, but with current and upcoming advances in manufacturing, such as 45nm chip production. And if not that route, it can definitely be upped in power and possibly the architecture improved and made more efficient, such as the evolution of the X86 architecture.

If anything, that route is likely the best bet for Sony, as developers will be familiar with the basic workings of the architecture, and while the newer features could be difficult to learn, it would be better than all that developers re-learning Playstation development again... even if it were similar to the next Xbox in terms of developer-friendliness. There are advantages and disadvantages to both routes, but in all honesty, Sony's best choice is continuing the use of the Cell architecture.

 

[hooflung]

For every PS3 chip not being utilized there is an Xbox chip not being utilized either. Stop being haters.

 

[magomago]

Originally posted by: Cogman
I have no idea what sony was trying to pull with the cell processor. Yes it makes a good super-computer processor but definitely not a good general purpose processor, or even a good graphics processor. (and really, there are now better choices for supercomputer processors now). They essentially doomed the PS3 from the beginning by saddling it with a processor that nobody could code for and an API that nobody could understand. All for the bragging rights to say "Well, we have 8 processors! What do you have, 2?"

So now you have this platform, with no really good games to start out with, and few games being planned for release. Nintendo released the Wii which was, you know, FUN to play. and Microsoft the 360 which gain a lot more developer support and hence more games from the git-go. But hey, you could own a black box that can play HD movies, and... Uh... Fold, yeah thats good.

2006 called - they want your fanboy self to stfu. This was an interesting thread till you decided to crap in it.