Not a possibility, as the MCM with the GPU and CPU is not an APU because of the two separate dies. APUs, including ones with HSA technology, have the GPU and CPU on the same die, which isn't the case on Wii U.

I think you've misunderstood the question.

It's not "what if the GPU has HSA technology in how it works with the CPU?" It's "what if the GPU also contains more CPU circuitry, and thus is closer to being an APU?"

After all, we've heard repeatedly that the GPU in the Wii U is meant to basically be a GPGPU, and my understanding is that AMD's HSA technology is meant to be their equivalent of a GPGPU, just in the form of an APU. It might explain why we've got so much conflicting information. I even see what I think is a plausible location for it - feature D on the annotated die image. Mind you, I'm no expert - I'm just looking for similarities between Llano and the Wii U CPU and GPU dies. There are some structures in D that resemble structures in the CPU part of Llano (the bottom part of this image), and aren't all that dissimilar to the right side of the CPU (this image), where the actual CPU components are (the left side has the memory). And if you compare the size of D with the size of the CPU cores (you can recognise them based on the fact that there are three cores, and the middle one has four times the cache), it actually comes out damn close.

It doesn't necessarily have to have any physical CPU core - just some of the logic, etc.

I think you've misunderstood the question.

It's not "what if the GPU has HSA technology in how it works with the CPU?" It's "what if the GPU also contains more CPU circuitry, and thus is closer to being an APU?"

After all, we've heard repeatedly that the GPU in the Wii U is meant to basically be a GPGPU, and my understanding is that AMD's HSA technology is meant to be their equivalent of a GPGPU, just in the form of an APU. It might explain why we've got so much conflicting information. I even see what I think is a plausible location for it - feature D on the annotated die image. Mind you, I'm no expert - I'm just looking for similarities between Llano and the Wii U CPU and GPU dies. There are some structures in D that resemble structures in the CPU part of Llano (the bottom part of this image), and aren't all that dissimilar to the right side of the CPU (this image), where the actual CPU components are (the left side has the memory). And if you compare the size of D with the size of the CPU cores (you can recognise them based on the fact that there are three cores, and the middle one has four times the cache), it actually comes out damn close.

It doesn't necessarily have to have any physical CPU core - just some of the logic, etc.

I think you've misunderstood the question.

It's not "what if the GPU has HSA technology in how it works with the CPU?" It's "what if the GPU also contains more CPU circuitry, and thus is closer to being an APU?"

After all, we've heard repeatedly that the GPU in the Wii U is meant to basically be a GPGPU, and my understanding is that AMD's HSA technology is meant to be their equivalent of a GPGPU, just in the form of an APU. It might explain why we've got so much conflicting information. I even see what I think is a plausible location for it - feature D on the annotated die image. Mind you, I'm no expert - I'm just looking for similarities between Llano and the Wii U CPU and GPU dies. There are some structures in D that resemble structures in the CPU part of Llano (the bottom part of this image), and aren't all that dissimilar to the right side of the CPU (this image), where the actual CPU components are (the left side has the memory). And if you compare the size of D with the size of the CPU cores (you can recognise them based on the fact that there are three cores, and the middle one has four times the cache), it actually comes out damn close.

It doesn't necessarily have to have any physical CPU core - just some of the logic, etc.

Keep in mind that I'm not saying that it does have it, or anything like it. I was primarily explaining what unaveragejoe was talking about, and then was inspired to compare CPUs with Latte, just to see if it could actually make sense.

As for why they'd have an AMD APU and an Intel CPU on the same MCM... the obvious explanation would be that the Intel chip can run the OS and handle backwards compatibility (GC and Wii both had Intel CPUs - note that Espresso is understood to have a very similar processor to the Wii in terms of core architecture), while the APU could handle games, with the CPU helping out where appropriate.

There's an interesting thing to notice about the Wii U's MCM and the location of the RAM around it - it's all much closer to the GPU than the CPU.

The large square on the MCM is the GPU, the smaller one is the CPU. The RAM is on the right side. Why position them like this? I'm not saying it's meaningful, because it very well might not be - but it could be evidence.

Essentially, the question is whether we're really understanding the architecture of the system. There are so many possibilities we haven't accounted for, yet, and this is just one of them. Note that there's also the question of the third chip on the MCM - what is that smaller chip (just below the GPU in the above image)? There's been some speculation, but nobody actually knows at this point.

Note that I looked at the CPU for inspiration when making the comparison - I also looked at Llano, which is an AMD chip, because it should more resemble that than the CPU.

Everyone compares to Llano, by the way... which is a 28nm APU. What if we compare with a 40nm APU like Zacate?

Look at the section marked "CPU Core". Now, compare with what we see on Latte, in section D. To me, there's definitely a similarity, although I can't be sure. I also see something similar in X. An interesting thing to note is that some, including that Marcan guy, have speculated that Y is the equivalent of the Wii's own CPU-core-on-the-GPU, Starlet, which people have taken to calling Starbuck as a dual reference to coffee and Starlet. Indeed, Y looks a fair bit like the "centre" part of the two CPU cores (the top half of the bottom core, and the bottom half of the top core) of Zacate, while the bottom part of X looks a lot like the other halves of the Zacate cores.

Anyway, it's food for thought.