In an interview with Digital Foundry, Raspberry Pi executive director Eben Upton claims that the little $25/$35 credit card-sized PC will crank out twice the performance of the iPhone 4S "across a range of content." He even trashes Tegra while comparing his home-grown GPU core to Nvidia's mobile solution.
"I was on the team that designed the graphics core, so I'm a little biased here, but I genuinely believe we have the best mobile GPU team in the world at Broadcom in Cambridge," he said. "What's really striking is how badly Tegra 2 performs relative even to simple APs using licensed Imagination Technologies (TI and Apple) or ARM Mali (Samsung) graphics."
"To summarize, BCM2835 has a tile mode architecture - so it kills immediate-mode devices like Tegra on fill-rate - and we've chosen to configure it with a very large amount of shader performance, so it does very well on compute-intensive benchmarks, and should double iPhone 4S performance across a range of content," he added.
Also in the interview he revealed that the Raspberry Pi can be overclocked, although users won't be able to push it more that 100 MHz above the current 700 MHz core clock speed. "The ARM is already fairly close to the edge at 700 MHz," he said. "Without overvolting the chip (which decreases lifetime), there's not much more than 100 MHz of overclocking headroom on typical silicon. We do offer a clock speed tweak option in the boot configuration parameters, so if you get lucky and get a fast part you can exploit it."
Upton also indicated that his team has talked with Microsoft about using Windows 8 on the device, but the upcoming OS will require an ARMv7 (Cortex) processor, and won't run on the Raspberry Pi's current ARM11 core. A future version might support the new Windows platform, as there seems to be a lot of interest in running Windows-based applications.
As it stands now, Raspberry Pi runs Linux which will play host to a wide range of programing environments. Already lined up for the credit card platform are Scratch, Logo and Kid's Ruby for younger children and beginners, and tools like YoYo Games' GameMaker. Raspberry Pi will also support fully-fledged professional tools like Python and C. Even XBMC runs "beautifully" on Raspberry Pi.
After years in development, the first production run of 10,000 units will be available for purchase within the next few weeks. The basic version will cost a mere $25, and the $35 version adds more memory and an Ethernet port.
