I have a doubt about the onboard computer in the AscTec Hummingbird.
In the web says The inertial guidance system provides highest precision through advanced sensor components and two ARM7 microprocessors.
The two ARM7 microprocessors are on the Hummingbird's AutoPilot. One of them - called the Low Level Processor (LLP) - is programmed by Asctec to perform low level controls using the inertial guidance system. The other ARM processor - called the High Level Processor - contains software written by Asctec, but you can modify this software to do your own controls or communications and some other things using the Asctec SDK.
In addition to the AutoPilot, you can mount an onboard computer to the Hummingbird (or other aircraft) that is just a small, low-power x86 PC. This is useful/necessary if you want to do advanced sensor processing using a camera or laser scanner, which you can't do using the ARM processors on the AutoPilot. Your second link is just showing that the Hummingbird is only compatible Asctec's Atomboard, and the Atomboard has an Intel Atom Z530 processor.
Personally, I would avoid the Atomboard. It's underpowered, expensive, and difficult to use (the LVDS display is awful). I would recommend buying your own small computer to mount, like an Odroid U3, Beaglebone, or Raspberry Pi. You might even be able to use an Intel NUC (I have one mounted to an Asctec Pelican).
By the way, we will release a new Atomboard (v3) shortly. It will feature a Quad-Core Atom with 1.91Ghz (E3845), GigE, USB3.0 aaaaannnd a DisplayPort connection :)
You are right, the LVDS display was a bit cumbersome.
I've seen that you mounted an odroid on your pelican. I'm trying to do the same, but it's an odroid xu4.
How did you connected your odroid to the power supply board?
I used to program the pelican with an atomboard, but it's powered with a 9V cable from the asctec power board.