Discussion in 'CellPerformance@B3D' started by one, Sep 20, 2007.
But as far as i understand, it can only work as PCI-e accelerator?
Seems so, it's a co-processor. Future CE products from Toshiba may incorporate it without PCI-e.
This is hilarious. Dedicated decode/encode chips instead of using Cell to do the whole thing
specialised cores will always be more efficient. But you are right, Cell was intented to be flexible yet efficient enough to replace specialised solutions as the "SpursEngine" (ie. good enough that the gains of specialised solutions stand in no relation of development costs).
So its quite ironic to see Toshiba themself come up with it.
I think part of it is that Toshiba itself has always been rather opposed to the inclusion of the Power core as it applied to their own purposes; beyond that, no need for a full Cell chip here since it's going to be an x86 laptop with a 'primary' CPU anyway. So, while you're cutting it down to begin with, might as well only keep as many full SPEs as you need and include lesser silicon for the functions which lesser silicon can perform.
I'm personally pretty excited about the development - it'll help push the SPE API forward into the CE space, where it should at least perform well comparatively, and it shows a spread if not of the chip then at least of the architecture. I'd love to see Toshiba sell this chip into the add-in board market, where vendors putting forth a little effort could make it both an A/V accelerator for video/imaging and a physics accelerator for gaming. Might be positive for workstation use as well. Toshiba recently demonstrated an SPE fabbed on their 65nm CMOS process; I imagine this chip is fabbed on such as well, so should be pretty cheap to produce.
Maybe people should remember what Emotion Engine also designed by Toshiba was like
MIPS core + DMAC + VU0 + VU1 + IPU (MPEG2 decoder)
Rough die size. The angle will throw off the estimation a bit, but.... good enough I say!
Interesting. Toshiba ditched the PPE that they never wanted in the first place! Not sure how this fits into their CE targets. Presumably they'll have an existing processor they're used to and add the SPEs alongside. On the plus side, it shows some flexibility with the Cell design, but on the downside it's not really advancing the family rather than creating a schism. Is it Cell if it's just SPUs connected to an arbitrary processor? If AMD were to integrate SPE's onto their next chip as coprocessors, would that make it a Cell? The lack of full IPA compatibility concerns me. Will this SpursEngine be able to contribute to a networked processing system as envisaged with Cell, with Cell devices working to augment each other? Or have they just created a standalone part for CE goods where Cell was too pricey? In that respect it is a smart move, as Carl says. It uses SPE code and promotes SPE development. Anything achieving that now has to be good for the long term health of the platform; it's better than not using anything Cell at all.
Yes, it is good news (and very important !) as long as they build up the software library and expertise for SPU development, and can compete with cheaper solutions in price/performance ratio. If deployed for real, the move will keep Cell viable and visible on the marketing front. I wonder if it make sense to have 2 SPE versions.
It is not so good news on the cost saving side (for people who thought they could repurpose the "broken" Cell chips for CE applications).
That might not be a cost saving choice. I mean, if all those broken Cells are lying around, it will be cheaper to use them than make some new chips nd chuck those Cells in the bin!
Could it be more a choice of power consumption and heat? SpursEngine is set to burn 10-20 watts. That sounds a lot less than you'd expect from Cell, although they're clocking much lower. What do we think a CBE with 4 working SPEs at 1.5GHz will consume?
A better comparison is with 5 working SPEs, the 5th one for MPEG2/H.264 processing. Or 6 SPEs, depending on the performance of the full-HD video unit in SpursEngine.
True. My guess is a 1:6 CBE would be running at least double the wattage.
Yap ! That's what I meant. Now they went to do another custom Cell chip. The "broken" Cells remain unused probably because of power consumption and cost (for CE deployment).
Meanwhile, as long as they continue to do more stuff using just 4 SPEs, a 7 SPE system like PS3 will gain more legroom as a result (e.g., Can run stuff in parallel while doing Blu-ray).
AFAIK the IPU doesn't decode MPEG2 by it self.
Yeah, let me correct it to "MPEG2 decoding accelerator" that does things like iDCT conversion, macro-block decoding, texture decompression etc.
That and the lack of PCI-E would make it problematic to use as an accellerator card. The market's pretty small when it comes to platforms that use Flex-IO, so reusing a bad Cell would require the use of some kind of specialty bridge chip (which also costs money).
Imagine the power and ground pins saved by shaving off most of Cell. I know if it's even possible to just not connect power and ground pins, even if half the chip is turned off.
Without per-core power planes, the chip might not function.
Is it even possible for Cell as it is used in the PS3 to initialize properly without the PPE active?
I wonder if the hardware makes some assumptions about functionality that would not be preserved if forced into this more specialized role.
It looks like Toshiba are serious about going commercial with their Magic Mirror.
If they can do it with just 4 SPUs at 1.5 GHz, the 6 available SPUs at 3.2 GHz in the PS3 Cell should run circles around that application. I am really looking forward to that demonstration.
Its a kick ass application, there is no doubt about that. I can see women the world over (my girlfriend being one of them) going crazy for this thing - I mean seriously crazy!! Hell, I think my gf would love the PC more than me if I had this on it!
But I do wonder, does it really need the spurs engine to work? Surely a 4 SPE 1.5Ghz processor can't be capable of anything a powerful desktop CPU isn't already capable of.
Are we saying a quad core couldn't run this as I would sure as hell rather invest in one of those than a seperate add in board?