Thursday, January 26th 2012
$25 Raspberry Pi Hobby Computer Doubles iPhone 4S GPU Performance And Beats Tegra 2
We have previously reported on the super cheap ARM-based Raspberry Pi hobby computer that's been under development from the Raspberry Pi foundation. However, it's now going into production and is generating a lot of interest, so gamesindustry.biz interviewed its founder, Eben Upton, about it (free registration required).
The computer's primary purpose is as a computer science teaching aid in schools and colleges and also for home brew use by enthusiasts who want to tinker with it and make specialized solutions out of it. However, it seems that enthusiasts will have a nice surprise in that the onboard GPU is surprisingly good. The actual ARM implementation is a Broadcom BCM2835 System on Chip (SoC) containing an ARM 11 CPU and a custom graphics core, which has been designed by the Raspberry Pi team, including Upton. In the interview, Upton claimed that it can double iPhone 4S performance and handily beats NVIDIA's Tegra solution, because of its tile mode architecture."Q: We know that you have a 700MHz ARM11 core in the Raspberry Pi SoC. However, you've described the Broadcom chip as a GPU with ARM elements grafted on. Can you give some idea of the rendering power of the graphics core? Is it true that it comprehensively outperforms NVIDIA's Tegra 2? If so, how?
Eben Upton: 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. 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 summarise, 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."
There don't appear to be any objective benchmarks to prove this at the moment, so we will have to take his word for it for now. Of course, this little computer isn't a one trick pony and can do many other things, such as offering full support for 1080p30 Blu-ray h.264 files, making it a competent media player. Also, it runs Linux, which is highly customizable and has a good selection of interfaces, such as USB 2.0, SD, HDMI, RCA video, analog audio and a 10/100 Ethernet port. It is also capable of supporting various expansion boards.
The computer's primary purpose is as a computer science teaching aid in schools and colleges and also for home brew use by enthusiasts who want to tinker with it and make specialized solutions out of it. However, it seems that enthusiasts will have a nice surprise in that the onboard GPU is surprisingly good. The actual ARM implementation is a Broadcom BCM2835 System on Chip (SoC) containing an ARM 11 CPU and a custom graphics core, which has been designed by the Raspberry Pi team, including Upton. In the interview, Upton claimed that it can double iPhone 4S performance and handily beats NVIDIA's Tegra solution, because of its tile mode architecture."Q: We know that you have a 700MHz ARM11 core in the Raspberry Pi SoC. However, you've described the Broadcom chip as a GPU with ARM elements grafted on. Can you give some idea of the rendering power of the graphics core? Is it true that it comprehensively outperforms NVIDIA's Tegra 2? If so, how?
Eben Upton: 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. 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 summarise, 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."
There don't appear to be any objective benchmarks to prove this at the moment, so we will have to take his word for it for now. Of course, this little computer isn't a one trick pony and can do many other things, such as offering full support for 1080p30 Blu-ray h.264 files, making it a competent media player. Also, it runs Linux, which is highly customizable and has a good selection of interfaces, such as USB 2.0, SD, HDMI, RCA video, analog audio and a 10/100 Ethernet port. It is also capable of supporting various expansion boards.