Among other things. My first question was, is the hardware open? Couldn't find an answer to that.
Edit: Apparently revision 2 of Purism will possibly have Coreboot.
The figures were about 1500 CPU-seconds for the desktop and 3000 CPU-seconds for the Chromebook. Of course, wall-clock time was significantly less for the desktop due to having many more cores, but that's showing that per-core, the high-end Intel was only about twice as fast as the ARM.
I do development work on the Chromebook, via a Debian chroot inside Crouton. And you know what? It's fine. It's probably the fastest laptop I've ever owned. The filesystem's a little slow, but compilation speeds are perfectly adequate.
Render Time:
Photon Time: 0 hours 0 minutes 1 seconds (1.256 seconds)
using 11 thread(s) with 1.456 CPU-seconds total
Radiosity Time: No radiosity
Trace Time: 0 hours 2 minutes 18 seconds (138.426 seconds)
using 8 thread(s) with 1099.214 CPU-seconds total
I would be very surprised if the Chromebook's 1.8GHz Cortex-A17 was only 3x slower. Googling around, I see people mentioning numbers like 10,000 CPU-seconds.
8x i7-3770K: 1123 cpu-seconds (wall-clock: 144 seconds)
4x Cortex A17: 3196 cpu-seconds (wall-clock: 963 seconds)
I just wish it had more cores, but I suspect that Rockchip are raking in money from these things, and I expect we'll get more cores next year.
The 12x Xeon was my work machine. I might have to have a word with them about it.