Revision as of 23:55, 19 September 2017

Template:mpu Scorpio Engine is a 64-bit octa-core x86 SoC designed by AMD and Microsoft for their Xbox One X. The chip features eight Enhanced Jaguar cores operating at 2.3 GHz and a custom Arctic Islands-based GPU operating at 1.172 GHz. Fabricated on TSMC's 16FF+, this chip supports 12 (24 for Dev) GiB of 12-channel GDDR5-6800 memory.

Overview

Like the PlayStation 4 and the Xbox One, the Xbox One X is also powered by a chip based on AMD's architectures. The Scorpio Engine most important goal was achieving true 4K gaming performance according to John Sell, a Distinguished Engineer at Microsoft who presented the chip at Hot Chips 29. Fabricated on a TSMC's 16 nm process, the chip contains 7 billion transistors on a 359 mm² die, similar in amount to Nvidia's GTX 1080 and almost the same size as the original Xbox One SoC (which was 363 mm² on a 28 nm process).

Like the original Xbox One SoC, the chip feature eight Jaguar cores. The cores have been lightly enhanced and operate at a higher frequency of 2.3 GHz, but are otherwise mostly identical. It's worth pointing out that AMD has not commercialized a 16 nm Jaguar processor outside of this chip.

Cache

Main article: Enhanced Jaguar § Cache

[Edit/Modify Cache Info]

Cache Organization Cache is a hardware component containing a relatively small and extremely fast memory designed to speed up the performance of a CPU by preparing ahead of time the data it needs to read from a relatively slower medium such as main memory. The organization and amount of cache can have a large impact on the performance, power consumption, die size, and consequently cost of the IC. Cache is specified by its size, number of sets, associativity, block size, sub-block size, and fetch and write-back policies. Note: All units are in kibibytes and mebibytes.

L1$ 512 KiB 524,288 B 0.5 MiB L1I$ 256 KiB 262,144 B 0.25 MiB 8x32 KiB 2-way set associative   L1D$ 256 KiB 262,144 B 0.25 MiB 8x32 KiB 8-way set associative write-back L2$ 4 MiB 4,096 KiB 4,194,304 B 0.00391 GiB     2x2 MiB 16-way set associative write-back

Memory controller

[Edit/Modify Memory Info]

	Integrated Memory Controller
	Max Type GDDR5-6800 Max Mem 12 GiB Controllers 12 Channels 12 Width 384 bit Max Bandwidth 304 GiB/s 311,296 MiB/s 326.418 GB/s 326,417.514 MB/s 0.297 TiB/s 0.326 TB/s Bandwidth Single 25.33 GiB/s

Graphics

Main article: Arctic Islands microarchitecture

Scorpio Engine features a 40 Radeon compute units (CU) operating at 1,172 MHz each capable of 128 FLOP/cycle for a total of 6.00064 TFLOPS raw peak performance. The GPU is capable of 4.688 Giga primitives/second and 187.5 G bilinear texels/second.

Display

Scorpio Engine supports DP 1.2a, HDMI 2.0b, HDCP 2.2, and two-stream MST. 4K, 64-bit, 3-surface resize and blending is supported.

Audio

8 custom processors.

Utilizing devices

• Xbox One X

This list is incomplete; you can help by expanding it.

Die

• TSMC's 16 nm FF+ process
• 7,000,000,000 transistors
• 359 mm² die size

Yield & redundancy

In normal microprocessors such as typical CPUs and GPUs, when a core in the case of a CPU or a shader unit in the case of a GPU has a defect, it's common for manufacturers to disable those affected cores/shaders (typically in a symmetrical way) and sell those chips as lower end models. Since the Scorpio Engine is only found in the single-specification Xbox One X machine, binning is not possible. In an attempt to improve yield the Scorpio Engine actually incorporates 11 Compute Units (CUs) in each shader array for redundancy, 10 of them are operational while the 11th one is used as a spare. With 4 shader arrays, there are 4 spares and 40 enabled CUs. If one or a few compute units are faulty but the rest of the chip is fully functional, the spare CUs can be enabled to compensate for this.