Nvideas rsx pipelines vs 360 ATI pipelines 360 core vs ps3 cell

Xenos has 48 Unified Shaders (Pixel or Vertex) while RSX has 24 separate Pixel Shaders and 8 separate Vertex Shaders.

Xenos has nothing in common with ATI's R5xx and is the basis for ATI's R6xx. Xenos' feature set is way past DirectX9 and closer to DirectX10/WGF2.0

http://www.beyond3d.com/#news28611

While RSX is based on G70, a strict DirectX9 part

http://www.beyond3d.com/#news29579

 

Xenos is closer, in actual fact, to DX9 - it is a composite of DX9 with some DX10 shader techniques and intelligent integration technology (simplified shader implementation). It is better known as the R500, and was originally to be launched on the PC instead of the 360... It was replaced by the R520 which is a differant part, made by a superior design team. R600 will have more in common with the R520/580 than the R500...
The Xenos uses 48 ALUs and can output to a limited 16 ROPs, which is fine. It is an inferior part to the x1900 in ters of technology and architechture, which should be expected of a part designed nearly a year ahead of the other...
The G70 uses a pipeline design that is more efficient at filling the screen with textures, but inferior when heavy shader operations are needed. This is because of the 24 pipelines with a shader unit each, which can paint more pixels, but do less shader passes...

Neither has a big advantage over the other, but if Cell can be used well later in the game then we may see better things from PS3, and with the purported price tags I would bloody well hope so!

 

hmm and i was expection my thread to boost in posts at e3 time lol

 

it seems that the cell is being multitaksed. for example some SPEs would handle phyics and some others would handle AI, volumetric calculations and so on.. at a detail level that would require a top of the line computer witha dedicated physics card

 

Perhaps, but new bottlenecks revealed in the memory subsystems mean that graphics will suffer compared to today's high tech PCs...

 

also the yeild has been rumoured to be under 70%

 

What difference does it make anyway?

You pays your money......
You makes your choice.....

 

Firstly, the 360 doesn't have 48 shader pipes, it has 48 shaders, and 3 pipelines. Meaning you can adjust shader/vertex performance 16 shaders at a time. ie. 32 pixel 16 vertex. In average pixel shading, the 360 GPU performs more like a 24pipe R420, but leaving room for massieve vertex/geometry processing (needed for dx10).

As for the ps3, nVidia pipes are MUCH more robust AND have more texture fetch units.

Also, that big turbocache to the XDR memory is there for a reason, the CELL can handle many of the vertex ops. Giving it either incredible vertex power, a big thing for dx10 specs. Or (a big rumour) leaving room for more pixel shaders by having no vertex shaders on the GPU (this would not have to affect the architecture, just more of the same stuff).

A note on the 360 CPU, it can do 6 threads, though most games in first gen ps3 and 360 will only use the traditional 1 thread, so for the first year or so, potential will not be fully realised on the 360 cpu, however, having only one general purpose unit on the CELL, this isn't so much of a difference.

However the performance is limited on 360 CPU in hidden ways. Firstly, the fact that the 360 only has a 9GB storage. To fit more content in games, textures are compressed. This generally requires one of the 6 threads dedicated to realtime decoding, leaving only 5. Also, the 360 doesnt have an nForce DD5.1 encoding chip. So one thread must be dedicated to that for most games. Leaving 4 threads in a fully functional game.

For the ps3, the two above tasks can be fully offloaded onto the SPEs, though really a ps3 doesn't need texture decompression. Also, as compilers for the CELL improve, there is less ill effect on the cpu due to lack of branching on the SPEs. New physics techniques are being coded that work just as fast without branch prediciton, making the SPEs fully usefull for physics, and some aspects of AI. Leaving the general cpu with much less load (general operations make up a small ammount of modern programs), giving the ps3 most of the general branch power it needs.

 

Correction, it could be 16 pipes (i forget how the 360 GPU is compared to normal ATI GPUs). But the rest of the informatinn stands.

Also to note, while the 360 GPU can do free aa at x2 and x4, at 1080p resolutions, i believe it is limited to x2? Also i think trying to do supersample aa in the 10mb cache doesn't work very well either, though i can't be sure.

 

Request for a closure.

Why was this thread brought back after no one posted since may 11th?

No offence guys but this will only make neph's life harder and result in another "which is better 360 or ps3" thread.We have discussed the specs in depth a zillion times.Get what you want based on facts.

The end.

 

Sos, i found it in google

 

So you signed up just for this?

Huh well welcome to afterdawn I hope you enjoy your stay.We have had alot of crazy fanboy fights resulting in people getting banned from the site.It's sad I know but people just can't control themselves enough to act civilized.Feel free to look around we could use someone with your knowledge.Bye now.

 

ok thx for replying neph.

@GMScribe Yeah that post was really good.The 360 has 3 pipes holy crap I didn't know that.I'm pretty sure my powercolor ati x800 gt is based on the R420 but I could be wrong.I'll have to check on that in a minute.

So in your opinion which is better the rsx and cell combo or the tri-core and ati combo?

I think the rsx and cell are better.The cell doesn't even need a gfx card to do the graphics tasks, but sony put it in because the cell is harder to program for or so I heard.

 

Honestly, i couldn't say for sure, as the RSX specs could vary greatly. Sony may have added more features, or removed them to save power and heat production. This is partly why ATI used a much simpler, generalised(unified) design for the 360, as traditionally their cards are very power hungry. The problem with the RSX will be that even though nVidia have better techniques at reducing heat than ATI on the manufacture level, they are still using dedicated pipelines and shading units, which whilst very powerful, produce a lot of heat by having separate components for everything. In fact I remember sony stating that they were unhappy with the heat levels from the RSX. Hopefully they just helped nVidia perfect the manufacturing process rather than cut down on features.

I personally think, that the RSX and CELL combo will prove to be the best, not just because of power (which i believe will be a very close call) but because of the flexibility. The CELL can do anything to a video stream with no effort, it can be used in the name of science, either in cool games or as a none gaming use for the ps3(imagine if SETI ran their screensaver program on every ps3 that will eventually be in the world. The RSX will be supported by the open standard open-gl, allowing for interesting advances in graphics, without the hidden walls of directX. Also, assuming the ps3 will support linux, it will supply animators / developers, in particular, students, with very powerful hardware for very cheap and promote use and developement of open standards, which need more interest to stay ahead of APIs like directX. Also by not having a limited 10mb frame buffer, it does at least give you more choises of AA methods etc.

The 360 is a good console, but i think the balance is not done well. The unified shaders are good to the extent, you can just throw anything at it and get top performance wether vertex or pixel heavy. However, at the moment, they sacrafise overall raw performance to be implemented, so now is not the time for them. The cpu is basically 3x the PPU core of the ps3. My problem with this is that it is a powerPC core. The powerPC core can not order its own instructions, making it very weak at pipelining operations (slow at excecuting a single thread), and its only use is for branch prediciton (IF statements), though it does make up for this partly by excecuting two threads at once, but not nearly enough.

This can be good for AI and physics, however, most of physics and AI also requires powerfull and fast vector/matrix operations. the VMX extentions help but aren't super efficient and don't accept microcode (where a highlevel command direct represents a lowlevel command), which leads to more instructions to accomplish the same task. With the CELL, the PPU has all these flaws, thankfully though, general operations(IFs, Loops, etc) require a very small ammount of modern cpu time, so it does not suffer from having only one core. That is provided you can offload onto the SPEs. Thankfully you can write AI and physics code that doesn't use much branch prediction but is just as fast. This is where coding for the CPU is hard. Developers with engines and techniques that use branch prediction must adapt. So the older ones are moaning

Actually programing for the SPEs is a quite simple concept to grasp, the only problem was a poor compiler and SDK at first, which since has become much better, if you want to have a look, go to IBMs website and download it, it requires fedora core 5 to run. I've been reading the programming guide for the CELL a bit, and on a C / C++ level it's very simple. You can imagine SPE operations as seperate programs(they are compiled on their own). The PPU issues them and then handles a bit of general code, meanwhile the SPUs run the programs. You can then time the loading / interaction of programs for best interaction because they always run for predictable time limits (there is a program to tell you how long they run for) becasue they don't use branch prediction (yup, that's the reason why). You then have to learn something like 10 new commands to use to define where you want operations to end up, main memory, spe memory, etc.

There you have it a mouthfull, but there it is lol. I would comment on features of the RSX but i really don't know what they'll be, except that its shaders are coded in the nVidia Cg language which is just like C with a few graphics specific functions, so is really easy to code for and the Cg compiler will automatically optimise your shaders for you. You can download the latest beta (the version the ps3 uses) off nVidia's website.

 

Wow thanks for that great insight.

Yes lets hope they don't take out features of the rsx and just improve the stability without dropping performance.I have an xbox 360 and despite the external psu it's EXTREMELY HOT! It's a notorious over heater so lets hope sony/ibm/nvidia can do a little better.

That's what I keep hearing is that the cell is simple but game developers who are used to programming on other consoles and pc games have found it a be a real pain and it takes longer which means they cost more to develope(because the longer it takes by the hour the more company has to dole out in work wages)so sony put in the rsx for it's more simple language and what people were used to.It wasn't the only benefit of the rsx though of coarse.

It would be a shame to see developers not taking advantage of the cell.My step dad is a programmer and he says half the people at his job don't have very good skills despite there huge pay check.They mess up lines in the code and then my dad has to go over them because of their ignorance.I think it's these same types that can't grasp the cell.As for me I don't know much code myself.

I'm not sure what type of linux distro they will use but I hope it's not to washed down.Sony has said they want to make it easier for homebrew etc so hopefully that tells us it will be nearly a full version.I think that linux would be great and open the door for many new possibilities in gaming and entertainment.

I hear the processor in the xbox 360 isn't used as much as people might think.Hade posted a pretty decent link not long ago about the cell being tested by scientists.Here it is...
http://www.lbl.gov/Science-Articles/Archive/sabl/2006/Jul/06.html

 

well i support Nvidia and by the way there r more cell in ps3 than 360s core

 

GMScribe good post

 

Lol if you have spent countless hours researching and posting on a thread, and someone said something like this, they would be pretty darn p**sed off. I'm not gonna bash or anything but jeese man, keep it to yourself.

And its my thread .


Lot's of stuff said while i was gone that i did'nt even know about thanxx you guys about this information.

and nice post XD
=)

 

hey kookoo its been a while. yeah i really hope this thread starts up again when the ps3 is released.