We feel for [Jeff Geerling]. He spent a lot of effort building an AI cluster out of Raspberry PI boards and $3,000 later, he’s a bit regretful. As you can see in the video below, it is a neat build. As Jeff points out, it is relatively low power and dense. But dollar for dollar, it isn’t much of a supercomputer.Of course, the most obvious thing is that there’s plenty of CPU, but no GPU. We can sympathize, too, with the fact that he had to strip it down twice and rebuild it for a total of three rebuilds. One time, he decided to homogenize the SSDs for each board. The second time was to affix the heatsinks. It is always something.With ten “blades” — otherwise known as compute modules — the plucky little computer turned in about 325 gigaflops on tests. That sounds pretty good, but a Framework Desktop x4 manages 1,180 gigaflops. What’s more is that the Framework turned out cheaper per gigaflop, too. Each dollar bought about 110 megaflops for the Pis, but about 140 for the Framework.So was it good for AI anyway? Predictably, no. While the Pi 5 does have an integrated GPU, llama can’t use the version of Vulkan for speedups. Even a cheap consumer PC can turn in better performance. The Framework without its GPU did about six or seven times better. With the GPU? Around 14X compared to the Pi cluster.Should you build it? [Jeff] says no, unless you have a very special use case for it. However, we build plenty of things that aren’t super practical. If you have a use for the beast, let us know in the comments.Even if your cluster isn’t as powerful as this one, you can still pretend it is a Cray. We wonder if ten Pi 5s can beat 1,060 Pi 3s?