The Race For A New Game Machine:. David Shippy

meeting to start. But a swirl of thoughts about Intel grabbed my attention. I knew Intel wasn’t sitting on its hands; their people were working, just as we were, to push the limits of technology. They had thousands of engineers working on their next chip, while we had a few dozen. I knew several former IBMers, smart guys, who moved to Intel, and I knew they were inventing cool new stuff for our enemy. How could we compete?

      Kahle waited for a quorum to gather, then stood and explained Hofstee’s mission and our job. He said, “You have to be paranoid when it comes to beating Intel. Basically, we need to attack with multiple weapons, because just having a higher frequency will not be enough to make Intel’s customers switch. This calls for an extraordinary new design offering an order-of-magnitude improvement in performance.”

      It wasn’t quite a battle cry, but it generated the right discussions. We batted around various strategies, scribbled ideas on the board, and argued about competing technologies, all the while lacing our language with words like frequency, throughput, process, and performance. Also, there was a new term in the industry to describe the raw frequency of a processor. It was called “fanout-of-four” (FO4), which described the number of gate delays in each pipeline stage or, more specifically, the number of simple inverter gates connected in series, each having a fanout or load of four gates connected to them. A smaller FO4 gate delay translates to a faster frequency. This new term provided us with a way to describe and compare processor speeds across multiple manufacturing technologies. Therefore, when a processor design migrated from, say, a 90 nanometer manufacturing process to the newer generation 65 nanometer technology, the FO4 gate delay would stay the same while the frequency (gigahertz) could increase. The Power4 processor I worked on had a 24 FO4 gate delay, which translated into a 1.1 gigahertz clock speed. That was the fastest in IBM. Intel had the current speed record in 2001 with an 18 FO4 gate delay, which translated into 1.5 gigahertz.

      The pressure was on.

      The need for low power really tied our hands. For the compact cost-conscious PlayStation 3, achieving the frequency of a PC with the reduced power budget of the game console would be a huge challenge. Game consoles are smaller than PCs and have less capacity to keep the chips cool, and games are very compute-intensive functions that tend to max out the processor usage. Higher power on the PlayStation 3 would lead to more costly thermal control techniques like fans and heat sinks, and the costs for those components were very hard to reduce over time. Kahle explained that Kutaragi’s aggressive cost-cutting strategy proved to be a huge money maker for Sony on previous products, so of course that would be the plan for this product too.

      The Sony architect, Takeski Yamazaki, said in broken English, “Seventy-five watts is the highest power the console can physically tolerate.” Heads nodded in agreement, all Sony engineers.

      I was skeptical. Most of the server chips and PCs I had worked on in the past were well over this 75 watt budget. We set our sights on designing the fastest microprocessor in the world, but could we still do it knowing that we faced this ridiculously low power budget? We didn’t know yet what raw frequency (measured in gigahertz) would describe the top speed of our microprocessor, but now we knew that, at least for the game console application, it would be constrained by this maximum operating power. What would happen if we failed to meet the power goal? Major malfunction resulting in either a hang or an automatic shutdown. Or picture little Johnny game-player running to Mom when his game console burned a hole in his desk. Or worse, console meltdown. The images weren’t pretty. The faster a chip runs, the more heat it generates, so to avoid a meltdown, we have to either remove all that heat, or run it at a slower speed. Two terms that don’t normally go hand in hand are high speed and low power. Seventy-five watts was going to be really tough.

      Still, I wanted to believe Kahle when he encouraged the team as we adjourned: “Guys, I don’t know how we’re going to get there, but we’re going to do it.”

      Dr. Hofstee was finally ready to present his competitive analysis to Akrout and the team. I had previewed the data during the course of his research, and I was anxious to hear the most recent stuff. He had studied the trends for chip frequencies, primarily dictated by Intel. Detailed graphs showed his predictions of what current and future technologies could achieve. Part science and part science fiction, his analysis was a combination of what the physics of technology could deliver and what smart engineering could achieve. Intel was always the benchmark. There was no other game in town.

      I had done some comparison studies in the past, much like Hofstee’s task, so I was well aware of what a struggle it was to compare the different microprocessor designs (apples and oranges) on the market. Each one, shrouded in secrecy, manufactured in a different fabrication facility, used a different process. Details were scarce. As much as the efficiency of the design, the silicon manufacturing technology also determined the achievable frequency for the chip. It defined the minimum size of the transistor, the fundamental switching device in a design. Transistors became smaller and smaller as technologies evolved, and smaller meant faster.

      We gathered in Akrout’s executive conference room with its subdued sage green against natural maple, smoky shaded windows, automatically dimming recessed lighting, and luxuriously upholstered chairs that swiveled, tilted, adjusted, and rocked into no less than twenty-four different positions. Hofstee prepared to present his work. Jim Kahle and I walked in together, both dressed in sandals and shorts in celebration of the last days of summer. I lounged in the back of the room as usual and tilted my chair against the wall. Kahle moved to the front of the room and sat across the table from Akrout, who was already warming up the crowd. He was in prime form, chatting with each attendee as he or she entered the room, laughing with Kahle, greeting those who were attending by phone. About twelve other technical leads and a few managers sat at the table or on either side of the room against the walls. Jim Warnock, a newly appointed Distinguished Engineer who had recently joined Akrout’s staff, flew down from IBM’s Research Division in Yorktown just for this meeting. All the attendees were IBMers and all were male except for Mickie Phipps, Kathy Papermaster, and Linda Van Grinsven, three of the managers who were now responsible for the multicorporation design teams.

      Akrout stood and put a hand on Hofstee’s shoulder. “I asked Peter to research our competition, and he is ready to present his findings. This is my first time to see his data, too. What do we have to do to beat Intel? Where do we set the bar? Listen closely, for you are the ones,” he paused to point around the room at us, “who will determine whether we succeed or fail at this endeavor.” Through a wiring hub in the center of the conference table, Hofstee connected his laptop to the top-of-the-line projector suspended from the ceiling above the table. He looked more like a college student than the veteran engineer he was. Tall and lanky, perfectly straight sandy-red hair cut fashionably long, an open expressive face. He rubbed long-fingered hands together and clicked the button to pull up his introductory slide. Years of experience standing before engineering students gave him confidence and style. He carefully worked his way through a series of charts and graphs, clearly and methodically building the case to support his conclusions.

      Akrout sat forward in his chair, intensely focused on the data Hofstee presented. Occasionally, he pointed to the screen and asked in his shortened version of English, “Why that?”

      Questions were raised, interruptions were tolerated. Hofstee captured our complete attention. It was a topic of extreme importance to each one of us, as the conclusion of this meeting could very well dictate our workload for the next two to three years.

      “When the STI project started in 2001,” Hofstee said, “the best of breed in the industry was the Intel Pentium4 microprocessor. It topped out at about 1.5 gigahertz in a high-end PC. That design has eighteen FO4 gate delays in the basic pipeline. However, an inner integer core in the Pentium4 executes at nine FO4, or twice that speed!” He illustrated this point with a detailed diagram showing how Intel’s design frequencies improved year to year. “Based on this data,” Hofstee concluded, “Intel could very well produce a microprocessor in the 2005 timeframe that could achieve nine to ten FO4 and over four gigahertz, so to be competitive in this timeframe, we need to match that frequency in our seventy-five-watt power budget. We need a ten FO4, four gigahertz frequency!”

      The room exploded. It seemed impossible!

      I