By the time Sony unveiled the PlayStation 4 at last night's press conference, the rumor mill had already basically told us what the console would be made of inside the (as-yet-nonexistent) box: an x86 processor and GPU from AMD and lots of memory.

Sony didn't reveal all of the specifics about its new console last night (and, indeed, the console itself was a notable no-show), but it did give us enough information to be able to draw some conclusions about just what the hardware can do. Let's talk about what components Sony is using, why it's using them, and what kind of performance we can expect from Sony's latest console when it ships this holiday season.

The CPU

We'll get started with the components of most interest to gamers: the chip that actually pushes all those polygons.

The PS4 eschews expensive custom chips like the Cell in favor of one of AMD's accelerated processing units (APUs). This APU shares surface-level similarities with the chips you can pick up for your desktop from Newegg or Amazon, but the details are very different: it combines eight CPU cores based on AMD's Jaguar architecture and a GPU capable of 1.84 TFLOPS of raw performance on the same die.

The choice to go with an AMD CPU makes sense for a few reasons—the company's chips don't have the best x86 performance, but they're generally considered to be "good enough" for most tasks, and it's also likely that Sony could extract a better price out of the small and troubled AMD relative to the still-dominant Intel. The company's experience in high-performance graphics also can't be discounted; Intel's graphics products have improved at an impressive pace over the last few years, but they still don't have what it takes to power a high-end game console.

However, this does have implications for the console's CPU performance. AMD's CPU architectures have largely lagged behind Intel's in both instructions-per-clock and performance-per-watt since Intel released its Core 2 Duo CPUs way back in 2006, and though price cuts have helped it stay more-or-less competitive at the low and middle sections of the market, it has been effectively shut out of the high-end CPU market for years now.

The eight Jaguar CPU cores in the PS4 are going to be even slower than AMD's flagship Piledriver architecture—Jaguar is AMD's follow-up to Bobcat, which is actually the company's low-power CPU architecture intended for use in netbooks, tablets, and other small computing devices. This isn't automatically a bad thing—Bobcat is already much faster than Intel's analogous Atom processors (and Jaguar will definitely widen that gap), and the Bobcat and Jaguar parts that make it into netbooks and tablets are more likely to be dual-core chips rather than the octo-core configuration in the PS4.

The upshot is that there's a fair amount of CPU performance here—nothing record-breaking, but more than enough to work with. But it does mean that developers who want to take full advantage of the PS4's CPU are going to have to optimize their games to be heavily multithreaded. Sony's development tools will probably help developers do this, and taking advantage of eight x86 cores is still likely to be less difficult than developing for the complicated Cell processor (note that one of Sony's refrains at last night's unveiling was all about ease-of-use for developers). Still, it's an interesting move given that most games on x86 PCs still benefit more from a few very fast CPU cores rather than many slower cores.

The decision to go with Jaguar cores over something based on Piledriver (or even Steamroller, Piledriver's follow-up) is almost certainly about keeping overall power consumption as low as possible, especially when the console is being used for non-gaming activities, as is becoming more and more common as game consoles morph from dedicated gaming machines to do-everything set-top boxes. Both Bobcat and Jaguar support fairly aggressive power gating, which can turn entire CPU cores off when they're not being used—if you're doing a task that's more demanding of the GPU or uses the PS4's "secondary custom chip" (more on that in a bit), the console can simply switch off all of the unused CPU cores, saving power and cutting down on the amount of heat being generated.

Finally, the x86 CPU has implications for backward compatibility: the PS4's internals are so far removed from the PS3 that software emulation isn't going to be possible, and including the PS3's internals in the PS4 in the same way that early PS3's included the PS2's chips to enable backward compatibility would add too much cost for too little benefit. Sony has suggested that it might offer to stream some PS3 titles à la OnLive or Nvidia's Grid server, and while cloud gaming has its own downsides (latency being the most notable) it's going to be the only way this new PlayStation will be able to play games made for its predecessor.

The GPU

We don't know the exact architecture of this GPU, but there are only a couple of likely candidates—either AMD's currently shipping "Graphics Core Next" (GCN) architecture (many of which originally came to market as Radeon HD 7000-series products), or a next-generation revision of the same architecture. It's difficult to tell which is more likely; the spec sheet that is circulating merely says that these chips are "next-generation," but out of context it's not immediately clear what generation it's "next" from. However, AMD's roadmap through the end of 2013 is largely composed of GCN-based products, so it's likely that the PS4's GPU will share most of its architecture with cards from AMD's Radeon 7000 lineup, albeit with some customizations and enhancements.

In either case, we know a few things, and we can infer some others. Sony is claiming that the GPU has 18 "compute units." Let's assume these are the same "compute units" as the ones used in the Radeon 7000 series, and that each unit is composed of 64 of AMD's stream processors, four texture units, and one render output unit (ROP). In a GPU with 18 compute units, you'd end up with 1,152 stream processors, 72 texture units, and 18 ROPs. This figure isn't directly comparable with any one of AMD's current desktop or laptop GPUs, but given the cited number of FLOPS, it should perform just a bit better than AMD's Radeon HD 7850.

The last generation of gaming consoles blew the doors off of currently available PC parts in terms of graphics performance, but the PS4 isn't doing that—the 7850 is a solid performer, but even compared to today's GPUs, its performance is probably best described as "upper midrange." That card does get you good performance for the price, though—Newegg currently lists 7850 cards starting at around $170. This compares favorably to the $400-or-so you'll pay for a higher-end Radeon HD 7970, for example, which is generally about a third faster than the 7850. Getting two-thirds of the performance for less than half the price is a solid value proposition and should help keep the price down (though we won't know that until Sony has a price to give us).

What does all this mean? Well, the PS4's SoC should be capable of some really impressive visuals at 1080p, even on 3D TVs, with more impressive results than the Radeon HD 7850 itself, since game developers working with consoles can always optimize their engines and games to squeeze more performance out of console hardware (a nice side effect of having a single, stable platform to target). GPUs have also become quite a bit better at certain tasks than they were in 2005 and 2006—modern GPUs have made great strides in lighting and particle effects, which should really help to combat the brown-and-grey color palettes of so many of this generation's games (see this excellent Gamasutra article to see the technical reasons why this has been such an issue). Newer GPUs can also take over some of the heavy lifting from the CPU for tasks like physics processing—remember, GPU-assisted computing technology like CUDA and OpenCL didn't even exist the last time we got new game consoles.

However, if you were expecting the PS4 to support 4K gaming, you were probably destined to be disappointed this time around—the very highest of the high-end graphics cards available today can deliver playable performance for today's PC games at 4K, but the days when this highest-of-the-high-end performance would be crammed into a console are over. Sony has said that the PS4 will support 4K output for video and photos, but if you get a 4K TV at some point during the PS4's lifespan it looks like you'll have to live with upscaled games, barring any sort of software update or developer trickery that enables it.