Microsoft took the stage at the recent Hot Chips conference to dish out a little more dirt on the SoC that will power the Xbox One. While we’ve known for some time that the console will use a custom-designed AMD SoC with eight Jaguar CPU cores and integrated graphics, many of the fine details remained a mystery – until now.
As it turns out, the GPU inside the Xbox One is very similar to the Tahiti GPU that powers the Radeon HD 7970 in terms of sheer die size. Both components are built on a 28-nanometer process by Taiwan Semiconductor Manufacturing Company. The Xbox One SoC is 363 mm² and contains five billion transistors while the Tahiti counterpart is 365 mm² in size and packs 4.3 billion transistors.
That information alone smashes some previous rumblings that the Xbox One’s SoC could be the largest chip ever produced. For reference, Nvidia’s GK110 GPU is loaded with 7.1 billion transistors and is 551 mm². It won’t set any size records but it should still be rather impressive.
Microsoft also pointed out during the presentation that the chip will contain 47MB of internal storage. Elsewhere, the Xbox One will use DDR3 system memory instead of higher bandwidth GDDR5 that Sony is using in the PlayStation 4.
Microsoft will offset this decision by using some fast eSRAM on the SoC die, a move that isn’t uncommon for them as they essentially did the same thing with the Xbox 360. It’s also similar to what Intel did with Haswell by adding 128MB of eDRAM on the GT3e package as L4 cache. This helped them overcome bandwidth limitations of the CPU socket and provide some very impressive performance with regard to integrated graphics.