Tablet Processor - Talk About Bay Trail

Slowly approaching the end of 2013; new, 2014, Intel is preparing to meet with a new generation of Atom processors (more precisely, SoC) for mobile devices and PCs, code-named Bay Trail. In this post we will compare the new chips with the previous generation and see how much they have moved forward. Most of us, of course, are interested in consumer characteristics - how much better and more fun will we live with Bay Trail?

The Bay Trail processor family consists of three groups. Processors with the letter N (N3000 - "Pentium" and N2000 - "Celeron") are designed for laptops, with the letter J (J2000 and J1000) - for desktop PCs. We are most interested in those with the letter Z - for tablets. There are also two series here: Z3700 - quad-core tablets for Windows and Android tablets and dual-coreZ3600 for Android tablets. All processors are made using 22nm tri-gate technology.

Consider what the processors of the Intel Atom Z3000 series are. Their main characteristics are as follows:

• 4 cores / 4 threads, 2 MB L2 cache; out of order execution of instructions
• Intel Burst (we'll talk about it below);
• support for 64-bit OS;
• new for Atom vector SSE4.1 instructions;
• support for dual channel memory LPDDR3-1067 (maximum 4 GB);
• the graphics core Intel HD Graphics with the same architecture as that of the Intel GPU in Core processors - 4 actuators (8 threads each);
• dynamic frequency of the graphics core, hardware acceleration of encoding / decoding;
• new virtualization and security technologies.

The general architecture of the chip is shown in the figure below (clickable). For clarity, we will make a comparative plate of the characteristics of the platform of the previous generation Clover Trail + (Atom Z2760) and Bay Trail. The most fundamental changes are circled in blue. Traditionally for this year, we see especially many improvements in the graphic part. Moreover, it is now fundamentally the same for Intel Core and Intel Atom. The graphic core that shares thermal power with the CPU has a turbo mode. DirectX11 and the OpenGL ES 3.0 API are now available on tablets! High resolution displays are supported (up to 2560x1600).









HD H.264 hardware encoding can now be performed with the highest quality profiles, while power consumption remains low. The hardware encoding of MPEG2 is also partially accelerated. The list of hardware-decoded media formats has been expanded: H.264, VC1, MPEG2, MVC, VP8, MPEG-4 / H.263, MJPEG.
Testing showed that the hardware transcoding of 1080p24 @ 23Mbps is performed at the same quality on the new Intel platform 3 times faster than on the iPhone 5!


Hardware noise filtering - before applying the filter and after

The video output subsystem has a flexible dual configuration that includes two digital DDI interfaces.



To save energy, the display uses Intel Display Power Saving Technology (Intel DPST) - brightening and improving the displayed image, due to which it is possible to reduce the brightness of the backlight. Reducing the power consumption of the display as a result is 20-50%.



The Bay Trail combo memory controller can work with both DDR3L-RS and LPDDR3. Dual-channel memory is supported, aggressive energy-saving algorithms are applied. The memory bandwidth in Bay Trail is twice that of Clover Trail!


Comparison of memory speed. Here (CLT +) = Clover Trail +, BYT = Bay Trail

The new camera module allows you to shoot 1080p60 video, equipped with a digital stabilizer. The developers managed to achieve a minimum delay when taking photos. The module allows you to connect two cameras with matrices from 8 to 13 megapixels. Comparison with Clover Trail, obviously in favor of a new generation

	Clover trail	Bay trail
Shooting video	1080p30	1080p60
Dual video	Not supported	Both 1080p30
Photo during movie shooting	Not supported	High Resolution Photo
Digital stabilization	Two axes	Four axes (+ rotation)

A lot has been done to increase the platform’s energy efficiency. And in one of the first places here is Intel Burst Technology 2.0 , which allows the cores to run faster than the standard operating frequency, if this does not violate operational restrictions on temperature, consumption, etc. Thus, one core can take away sporadic load from others, reducing overall energy consumption. In the new version of Intel Burst, load balancing can occur not only between computing cores, but also graphic ones, as well as a subsystem for processing images from the camera and display.
The animated diagram below shows how the technology works:



Finer manufacturing process, architecture optimization and new technologies allowed achieving 2-6.5-fold increase in processor performance (depending on the application) with a significant reduction in consumption. This means that in 2014 we will see powerful, long-playing mobile devices on the Intel platform - according to the developers' forecasts, it’s real to talk about 8-10 hours of video playback for Bay Trail.

In preparing the post, IDF 2013 materials were used, written by Shreekant (Ticky) Thakkar.