A5X Proxessor vs Tegra 3

[iHuman1337]

I was informed by someone on Hacker News that when NVidia says this they are referring to SIMD units, of which the Tegra 3 GPU has 12. Apparently the GPU in the iPad 2 (I believe he was referencing the 2) has 16 SIMD units.

And people say Apple's marketing is misleading...

 

[tsekh]

Apple ran the PowerVR SGX 543MP2 in its A5 SoC at around 250MHz, which puts it at 16 GFLOPS of peak theoretical compute horsepower. NVIDIA claims the GPU in Tegra 3 is clocked higher than Tegra 2, which was around 300MHz. In practice, Tegra 3 GPU clocks range from 333MHz on the low end for smartphones and reach as high as 500MHz on the high end for tablets. If we assume a 333MHz GPU clock in Tegra 3, that puts NVIDIA at roughly 8 GFLOPS, which rationalizes the 2x advantage Apple claims in the chart above. The real world performance gap isn't anywhere near that large of course - particularly if you run on a device with a ~500MHz GPU clock (12 GFLOPS):

http://www.anandtech.com/show/5663/analysis-of-the-new-apple-ipad

That being said, you won't see games on the iPad 3 looks significantly faster or play significantly smoother than games on iPad 2 or Tegra 3 tablets. First, those numbers are theoretical output and in practical the difference won't be that large. Second, those numbers are in terms of raw processing power. The iPad 3 needs this much of GPU power in order to maintain the same framerate in running games when compared to the iPad 2. So resolution aside (which is a big difference, I'm not discounting it), you won't see a generational difference between iPad 2 and 3 in running games, the same for Tegra 3.

Modern games need a lot more than pure GPU power to run smooth. A lot of physics and AI calculation are happening in the background too, and the CPU plays a huge role here. Previous I thought, by staying with dual core and not quad core, Apple must have put the newer Cortex A15 CPU in the A5X. But after reading Anand's article, and his analysis of what's going on with other ARM licensees, that seems pretty unlikely. So the A5X has 2 Cortex A9 cores, and the Tegra 3 has 4 (plus a underclocked 5th A9 core). The A5X has better GPU, but outside graphically heavy apps, i.e. 3D games, the Tegra 3 has the advantage. This advantage will show up in heavily threaded apps, like the broswer, and especially the broswer. You can easily find video showing how the Android broswer takes advantage of the Tegra 3 and loads up pages faster than other dual-core SoC.

That being said, Tegra 3 won't show up in the iPad and A5/A5X won't show up in any Android tablet. So no one should really need to care which one is faster. It's not like you can choose between them anyway. And if you are choosing between the iPad and other Android tablets, solely base on the SoC they employ, you are making the wrong decision.

 

[Buildbright]

The snapdragon s4 pro with the adreno 230 looks like it might be the answer for android. I think the Tegra 3 is a letdown way over hyped.

 

[iHuman1337]

http://www.anandtech.com/show/5663/analysis-of-the-new-apple-ipadModern games need a lot more than pure GPU power to run smooth. A lot of physics and AI calculation are happening in the background too, and the CPU plays a huge role here. Previous I thought, by staying with dual core and not quad core, Apple must have put the newer Cortex A15 CPU in the A5X. But after reading Anand's article, and his analysis of what's going on with other ARM licensees, that seems pretty unlikely. So the A5X has 2 Cortex A9 cores, and the Tegra 3 has 4 (plus a underclocked 5th A9 core). The A5X has better GPU, but outside graphically heavy apps, i.e. 3D games, the Tegra 3 has the advantage. This advantage will show up in heavily threaded apps, like the broswer, and especially the broswer. You can easily find video showing how the Android broswer takes advantage of the Tegra 3 and loads up pages faster than other dual-core SoC.

Wait, where, in that article, did it talk about Cortex-A15 chips and licensing? Just curious, since I can't find any mention of it. Also, I highly doubt that Apple is going to upgrade the iPad without beefing up the CPU as well. At the very least I'm thinking it's higher clocked or, at best, a Cortex-A15.

 

[Buildbright]

http://www.anandtech.com/show/5663/analysis-of-the-new-apple-ipad

That being said, you won't see games on the iPad 3 looks significantly faster or play significantly smoother than games on iPad 2 or Tegra 3 tablets. First, those numbers are theoretical output and in practical the difference won't be that large. Second, those numbers are in terms of raw processing power. The iPad 3 needs this much of GPU power in order to maintain the same framerate in running games when compared to the iPad 2. So resolution aside (which is a big difference, I'm not discounting it), you won't see a generational difference between iPad 2 and 3 in running games, the same for Tegra 3.

Modern games need a lot more than pure GPU power to run smooth. A lot of physics and AI calculation are happening in the background too, and the CPU plays a huge role here. Previous I thought, by staying with dual core and not quad core, Apple must have put the newer Cortex A15 CPU in the A5X. But after reading Anand's article, and his analysis of what's going on with other ARM licensees, that seems pretty unlikely. So the A5X has 2 Cortex A9 cores, and the Tegra 3 has 4 (plus a underclocked 5th A9 core). The A5X has better GPU, but outside graphically heavy apps, i.e. 3D games, the Tegra 3 has the advantage. This advantage will show up in heavily threaded apps, like the broswer, and especially the broswer. You can easily find video showing how the Android broswer takes advantage of the Tegra 3 and loads up pages faster than other dual-core SoC.

That being said, Tegra 3 won't show up in the iPad and A5/A5X won't show up in any Android tablet. So no one should really need to care which one is faster. It's not like you can choose between them anyway. And if you are choosing between the iPad and other Android tablets, solely base on the SoC they employ, you are making the wrong decision.

Well since no one has any solid proof this holds no merit. Do you think Apple would put a inferior chip in there new flagship product. 1000 people at Apple work on there processors and thats just in house. So at least wait til you have some real proof.

 

[tsekh]

Wait, where, in that article, did it talk about Cortex-A15 chips and licensing? Just curious, since I can't find any mention of it. Also, I highly doubt that Apple is going to upgrade the iPad without beefing up the CPU as well. At the very least I'm thinking it's higher clocked or, at best, a Cortex-A15.

Page 2. But since you are too lazy to read, here is the quote

TI was one of the earliest partners with ARM on the Cortex A15 and silicon just came back from the fab at the beginning of this year. Even if Apple were similarly instrumental in the definition of the Cortex A15 architecture, it would be Q3 at the earliest before it could have working silicon available in volume. With no A15 design ready and presumably no desire to jump into the custom-designed ARM CPU market quite yet, Apple once again turned to the Cortex A9 for the A5X.

That's not a proof, but Anand is one of those people you can take his words for it. Moreever, Cortex A15 is a big deal. If Apple did make the move to Cortex A15, they wouldn't just leave it out and not mention it in the keynote (and somehow decided to talk about "quad-core" graphic instead).

Qualcomm is ready to ship Snapdragon S4 with Krait core, which is their custom design Cortex A-15 class SoC. But so far no ARM licensee is scheduled/ready to ship any Cortex A15 based SoC in the first half of 2012 yet. And given the volume that Apple needs in order to couple the new iPad with it, it is very unlikely that the A5X has Cortex A15 in it. Plus, the gigantic performance gain moving to Cortex A15 fully deserves the name A6.

 

[iHuman1337]

Page 2. But since you are too lazy to read, here is the quote

I wasn't too lazy to read, I just didn't notice it.

 

[aznguyen316]

>The iPad3 has a ridiculous amount of pixels to push for gaming!

If a game can't get the framerate they need at 2048 they can scale back to 1024 using pixel doubling. The resulting image will be no worse than it is on the iPad 2 but probably much smoother.

Honestly, I'll be shocked (in a good way) if many 3d games are actually going to run at 2048. If so, they'll look amazing.

Agreed this will probably be the case. When I used to game on my mbp I often would simply lower the res, keeping aspect ratio but turning up the graphics to the best it could handle. I had the hires AG panel so going down to 1280x800 helped fps a lot.

Basically I expect most 3d games to be deveoped with the res of iPad 2 with significantly more graphical details and effects (commonly done with console games as rarely any are even natively 720p, simply upscaled from 540p). I'd probably prefer it this way than native resolution 3d games. Give me 60fps and shader effects upscaled to retina over low gfx and 2048 res almost any day. However this does not mean that I wouldn't love to see the standard 2d games upscaled to the beautiful retina ( angry birds, PvZ, cut the rope, etc etc). I feel that could be possible.

 

[apolloa]

This is not an Apple VS Tegra was. It is an Arm Cortex and PowerVR VS Nvidia war.

And in that sense, the Arm and PowerVR will win as it is way more power efficient. It doesn't need millions of cores to achieve the same level of performance and reduce battery life!