At Quakecon 2013, John Carmack of Id Software (Doom, Quake, Rage) has spoken out about the PS4 and Xbox One, saying that their hardware is “essentially the same.” This comes at an interesting time, as Microsoft has just boosted the Xbox One’s GPU to keep up with the PS4’s significantly (~50 per cent) more powerful GPU.
In the same keynote talk, Carmack makes two other interesting observations: Three or four years ago, he thought that Intel would make a play for the console space with its stillborn Larrabee GPU – or, alternatively, that the Xbox One and PS4 could easily have been based on “super-mobile architectures”, with “16 ARM cores” and “a whole bunch of PowerVR graphics cores.”
“It’s almost weird how close they are,” Carmack said of the Xbox One and PS4, which are both equipped with a virtually identical AMD CPU and GPU. “Whether they converged intentionally, or if they were surprised that they wound up having almost identical specs.”
We’re fairly certain that the near-identical architectures are a coincidence, but a happy one for consumers and developers alike: By standardising on x86 hardware, it will now be cheaper and easier to develop games that span multiple platforms (consoles and PCs), with the knock-on effect that the average quality of games should improve as developers can spend more time focusing on the games themselves, rather than fiddling around with architecture-specific foibles.
Earlier this week we heard about Digital Foundry’s interesting, but perhaps not very informative, benchmarking of “simulated” Xbox One and PS4 hardware. The results show that the PS4 GPU’s 50 per cent-more-compute-units can provide a performance boost of around 25 per cent over the Xbox One.
If we dig into Carmack’s words a little more, he doesn’t explicitly say that their performance is exactly the same, but rather that their “capabilities” are. Basically, both consoles have access to the same shaders, the same OpenGL 4.2 and DirectX 11.1 support, and so on. The PS4 will almost certainly be faster than the Xbox One (even after the Xbox One’s modest GPU MHz bump), but the real-world difference will probably be negligible.
Carmack’s comments about Intel’s Larrabee are a bit of a surprise. He admits that, three or four years ago, he thought that Intel might make a huge play for the console market, possibly manufacturing Larrabee-based parts for Sony and Microsoft at a price point that they couldn’t refuse.
Larrabee was an interesting GCGPU architecture that attempted to use a mass of small Pentium CPU cores to provide the kind of parallelism offered by Nvidia and AMD’s GPUs. For a variety of reasons, Larrabee sadly never arrived; instead, Intel performed a “strategic reset” and used the Larrabee tech to create Xeon Phi, a high-performance computing add-in card.
If you thought that Carmack was slightly off-base with the Larrabee idea, his speculation that the eighth-generation consoles could’ve been powered by ARM is perhaps slightly more realistic. Head-to-head, ARM CPUs and GPUs obviously can’t compete against x86, but if you cram in enough CPU and GPU cores, you could create an ARM-based console with acceptable performance. This would have the added advantage of making the consoles consume less power, and probably cost less. Presumably there would be an easier porting path from ARM-based smartphone and tablet games to the consoles, too.
Neither of those alternate histories came to pass, though. For the foreseeable future, AMD has won itself a seat at the gaming table. As Carmack points out, with every developer optimising their games for the AMD APU in the PS4 and Xbox One, and thus PC games too, AMD might once again become a viable alternative to Intel in the PC gaming space.
For a lot of insightful commentary on the games industry, be sure to watch Carmack’s entire keynote (skip to 14:30 in the video above for the start of Carmack’s speech, and that’s just part one of it, of course). Kinect haters in particular will love Carmack’s comment that “Kinect is sort of like a zero-button mouse with a lot of latency.”