PALO ALTO, Calif. — The battle over big iron servers was the main event at this year's Hot Chips, an annual gathering of top microprocessor designers. But there were a few surprises along the way along with the occasional insight spicing up lunch under the eucalyptus trees on the Stanford campus.
I pulled out a few slides and observations on the next pages, starting with overviews of the impressive server processors -- IBM's Power 8 and Oracle's M6. These were both first, fairly in-depth looks at chips running in the lab but yet to ship into the market.
On the client side, Intel and AMD gave deep dives on their currently shipping processors -- Haswell, Kabini, and Richland -- no surprises there. Keynotes sparked discussions on two evergreen themes -- the end of CMOS scaling and the rise of patent suits.
When we weren't talking about how the technical or legal skies were falling on our heads, there were a few fun discussions over lunch and breaks. A Broadcom engineer regaled us with tales of his new Pebble watch that can preview text message and provide caller ID via Bluetooth.
I also had the chance to catch up with Brian Holden, who can now say more about that secretive startup he had just joined when I saw him at Hot Chips last year. Kandou Bus is developing algorithms for three-wire interconnects it claims will enable new capabilities and efficiencies for links such as 400 Gbit/second backplanes.
Now that PCI Express Gen 3 has pretty much been universally adopted in next-gen CPUs, Holden's former job as head of the Hypertransport consortium has pretty much wrapped up, giving him time to promote the Kandou technology in places like the IEEE 802 Ethernet committees.
Seeking the story behind the silicon, I took a few minutes to interview the engineers behind the custom chips in the Microsoft Xbox One. Patrick O'Connor, the senior engineering manager behind the latest Kinect sensor, recalled the day his team won a bake-off Microsoft held between three or four external time-of-flight sensors and the one his team proposed.
"For an engineering group, it's a big day when you essentially get a design win," O'Connor said during a morning break. "We were proud of our prototype, it was working beautifully and when we demoed the prototype it exceeded what anyone else was showing them," he said.
The 512 x 424 pixel sensor, made in a 130nm TSMC process has a 90 degree diagonal field-of-view and was part of a two-year development project on the next-gen Kinect.
"You can get really close to the camera and still detect a person in a normal living room where there is not a lot of space or light," O'Connor said. "You can also detect a child's hand or wrist even when they are far away from the camera, using just a few pixels," he said.
The net result is "much more accurate" game play. For instance, in popular videogames such as tennis, "you can put spin on the ball now because we see more subtle motions of wrist turns," he added.
Another Microsoft engineer said the company also held a bake-off to determine which CPU core it would use. It looked at all the usual suspects and some unusual ones including an internally designed instruction set before choosing the AMD Jaguar.
The following pages show key foils on the IBM Power 8, Oracle M6, Intel Haswell, and more.