Addendum:

> Raptor Engineering Inc. pre-announces Talos, an OpenPOWER ATX workstation
> mainboard for 3100 USD. [...]

The minimum production quantity (and thus number of pre-orders) would be 2000 pieces according to this article:

http://www.techrepublic.com/article/why-the-talos-project-wants-to-provide-an-open-and-expandable-power8-workstation/