Cell and GPU work better together than either alone

Soldato
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Thought this was quite an interesting read, although tbh most of it went completely over my head.

PS3FANBOY.COM said:
The subject line is based on a series of facts, with hard numbers, released by a report by Sony themselves regarding the PS3's deferred shading and rendering. This is a detailed, confusing report, so if you're not a really techno-savvy lord with other techno-geeks buying you groceries or rubbing your hands to ease the twitch-reaction from all the mousing and keyboarding, it might go over your head. But for those with a keen interest in algorithms and the PS3's abilities, this is a delight to read and proves, ostensibly, the PS3 can generate processing power and graphical ability beyond a doubt above non-hybrid structures.

To help understand the numbers, graphs, charts, and whatnot in the report, we're going to use the abstract summary at the beginning of the report to show how the PS3 is proving its muscle through facts, not fanboyism. They summed the report up with this: "The SPEs use the Cell/B.E. DMA list capability to gather irregular fine-grained fragments of texture data generated by the GPU. They return resultant shadow textures the same way. The shading computation ran at up to 85 Hz at HDTV 720p resolution on 5 SPEs and generated 30.72 gigaops of performance. This is comparable to the performance of the algorithm running on a state of the art high end GPU. These results indicate that the Cell/B.E. can effectively enhance the throughput of a GPU in this hybrid system by alleviating the pixel shading bottleneck."

It seems there is a reason behind devs choosing to stick with the 720p resolution if that's the case. You can download the report and check it out for yourself here if you'd like and draw your own conclusion, but we think this tells us the PS3 made the right decision in creating a hybrid solution with the Cell and GPU. Leave us your take!

http://research.scea.com/ps3_deferred_shading.pdf

Whilst I get the jist of some of it - if any of you who fully understand this report wouldn't mind putting some of it into laymans terms it would be very much appreciated ;)
 
Smells like bait to me :rolleyes:

I'm not trying to bait anyone. I am really interested in finding out more about this report in 'man on the street' terms.

So if anyone wants to do 360 vs PS3 comparisons, wants to troll, flame bait or use this article to have a pop at Sony or MS then keep it for another thread.

;)
 
For comparison - The Physx card improves physic calculations on the PC. It has not be successful.

If the PS3 is uber powerful it really is irrelevant if it is not actually being utilised.
 
Whilst I get the jist of some of it - if any of you who fully understand this report wouldn't mind putting some of it into laymans terms it would be very much appreciated ;)

From what I can gather, the cell can be programmed process shaders like the GPU does. So in effect you have two graphics cards for shader effects.

Interesting stuff actually, because if there's anywhere the PS3's RSX lags behind the 360's Xenos, it's in shader horsepower.
 
The jist of it is that certain complex functions such as shadows can be offloaded onto the Cell SPE's which are actually able to computate them faster than RSX can, this will result in either a boosted frame-rate as the RSX will have less to render or alternatively allow developers to add a lot more detail as the RSX is free to do other things.
 
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Interesting stuff actually, because if there's anywhere the PS3's RSX lags behind the 360's Xenos, it's in shader horsepower.
Really, I didn't realise that.

I have heard several times that the GPU can tap into the system memory, so I guess that what they really meant was that the Cell can be used for GPU functions and use system memory.

Do shaders need much memory or is that just for textures etc?
 
It is not the same as a PC, CPU's are generally very bad at doing GPU 'stuff' and it looks like the Cell CPU is a bit different that it can actually be used effectively.
 
Sounds really interesting, do any of the ps3 game currently avalible use this to great effect already or is it something they are going to utilise in future releases?
 
For comparison - The Physx card improves physic calculations on the PC. It has not be successful.

If the PS3 is uber powerful it really is irrelevant if it is not actually being utilised.

That's because it costs over a hundred pounds and the uptake is (not surprisingly) low, so the developers don't bother using it much, if at all.

In the PS3 it's included in the overall price and will be in every console so the devs don't care about programming games to use it but keeping compatibility for PCs without a physx card...they can just use it without worrying about anything like that.
 
not unless every other PC or console has a CPU which was originally designed to handle GPU operations as well!!!

As proven by 3DMark in every iteration I have seen run

One section uses CPU power to generate the graphics, and I dont think I have even seen this test hit 2fps even on a 3Ghz q6600 / 4Ghz C2d at relatively low res.

I wont bother reading the report because even the qoute went over my head but its still interesting to hear - to me anyway
 
so is it this that make the ps3 so hard to make games for then?

all wel and good have the technology but if its so hard to use that people are priced out of doing so then its obselete
 
I guessed this is how it would work. I think Sony's original plan was to not have a GPU and get the Cell's SPEs to process graphics, but they realised that wouldn't do if it was to compete with the 360. So it makes sense that the Cell is fairly good at doing the same work as a GPU, so really the only question was whether there was enough bandwidth between the two so it could effectively take on some of the workload.
 
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