Marketing talk from Microsoft and Sony: The processors inside these machines are extremely powerful and cutting edge you literally have a supercomputer in your home as the Xbox 360 has 1 Teraflop worth of computing power and the PS3 has 2 Teraflops worth of computing power.

TRUTH: Both the 360 and PS3’s CPUs are heavily stripped down compared to what most of us are probably using on our desktop computers to view this article. Both consoles are labeled as 3.2GHZ, but they don’t offer performance comparable to that of a typical Athlon 64 3200+ or better than even an Athlon XP 2800+ CPU. The CPUs inside the Xbox 360 and PS3 are “In-Order Execution” CPUs with narrow execution cores, whereas what we use on our computers are classified as “Out-of-Order Execution” CPUs with wider execution cores.

The reason they can sell for so cheap is because they are not as robust or complex as what we have inside our computers. The execution theme in both the 360 and PS3’s CPUs is similar to that of what you would see in the original Intel Pentium Processor. (Not referring to the Pentium 2 3 or 4, but the original) This is because they’ve stripped out hardware designed to optimize the scheduling of instructions at runtime. As a result, neither the 360 nor PS3’s CPU contain an instruction window. Instead, instructions pass through the processor in the order in which they were fetched; hence both are “In-Order Execution” CPUs.

Marketing talk from Microsoft and Sony: Thanks to these multi-core processors developers will be able to multi-thread their games and get significant performance improvements and achieve Artificial Intelligence in games that people previously thought impossible for a videogame. It’ll be as if you’re playing with another living breathing human being.

TRUTH: “What is the big deal? How exactly does the fact that both processors being “In-Order Execution” CPUs hurt them? Well, see the 3.2GHZ clock speed for both CPUs? The type of nasty game code, full of branches, loops etc… that would’ve been greatly improved speedwise, thanks to out-of-order execution and a wider execution core is not there to help, so that 3.2GHZ actually performs slower than out-of-order execution CPUs available to desktop computer users.

This brings us to the very reason why both the PS3 and Xbox 360 are using multiple processors in an effort to combat the lack of an instruction window and the fact that they have a narrow execution core. It gets even better, because this very same code that they hope to speed up using parallelism on multiple cores isn’t by any means parallel programming friendly.

On the other hand, Graphics-related code is great on both these processors, as graphics code is nice and parallelism friendly. There is a reason people consider graphics accelerators to be the poster child for parallelism. As a matter of fact, it’s the most successful form of parallelism the field of computer science has ever witnessed. GPUs are able to get all transistors firing that actually produce a significant real world benefit to the people using the product.

For the CPU to become more like the GPU is the ultimate goal for many and AMD together with ATI seem to be going for it. The cell processor is actually one such attempt to do so, but it’s not yet at the level everyone had hoped. (Perhaps a bit early as a cell like CPU isn’t on Intel’s to do list until about 2015) Long story short, both Microsoft and Sony have given developers more than enough on the graphics side of things, but at the same time, are asking developers to do more with less on the aspects of the game unrelated to graphics.