What hash rate can a Raspberry Pi achieve? Can the GPU be used?

Question

A Raspberry Pi is a credit card sized $25 (or $45, for the deluxe option) computer, designed for educational use. Has anyone tried running mining software on it? If so, what's the hashrate like? (apparently the CPU is approximately equivalent to a P2 300MHz - I know the hashrate will be very low!)

Also, can the GPU be used to mine? What's the hashrate for that, if it's been done.

From the FAQ on the above linked site: "The GPU provides Open GL ES 2.0, hardware-accelerated OpenVG, and 1080p30 H.264 high-profile decode. The GPU is capable of 1Gpixel/s, 1.5Gtexel/s or 24 GFLOPs of general purpose compute and features a bunch of texture filtering and DMA infrastructure. That is, graphics capabilities are roughly equivalent to Xbox 1 level of performance. Overall real world performance is something like a 300MHz Pentium 2, only with much, much swankier graphics."

Note: The price of $25 or $45 excludes a way of powering it (via MicroUSB), a keyboard, a mouse and likely a USB hub. I think you need to provide an SD card too.

Answer 1

The Raspberry Pi uses the VideoCore IV series of GPU, which to my understanding are either a single or dual core GPU running at or around 700 MHz. Since the primary benefit of GPU mining is that you can run many parallel processes on the hundreds of cores typically found in most GPUs, the single-core nature of the VideoCore GPU undoes most of that benefit.

I don't have exact numbers, nor the necessary knowledge to compute an estimate, but I can tell you that the Folding@Home folks already discussed this and came to the conclusion that an AMD Phenom II X4 940 was almost 5 times as efficient for their needs as utilizing both the CPU and GPU of the Raspberry Pi. Since the needs of Folding@Home are very similar (but not identical) to Bitcoin's, it's probably not a stretch to say that if CPU mining (admittedly with a fairly nice CPU) is 5x more efficient, the Raspberry Pi doesn't look like a strong contender.

Of course, until we have solid MH/s and actual at-the-wall wattage numbers it's very difficult to say if, at scale, a cluster of $35 Raspberry Pis could compete with other setups on initial price or power cost. Personally, I'd guess not.

Answer 2

It gets less than 200kh/s on the CPU proof here http://www.youtube.com/watch?v=rrdzam7voOg&list=UUdOgdYMe-hwv2_uUtYlqLDQ&index=1&feature=plcp

Answer 3

There is a nice wiki page here: https://en.bitcoin.it/wiki/Mining_hardware_comparison

The raspberry pi is listed by its processor in the arm section: ARM1176JZ(F)-S. It gets 0.2 Mhash/s when clocked at 800 MHz.