I tried several, ranging from FreeBSD, FreeNAS, and PCBSD, to name a few.... and all of them lead me to the dreaded mountroot prompt....
Strangely, ONLY PCBSD's forums seem to have the answer prominently posted.
Was there a certain version where this became a problem?
The motherboard I am using has VERY few options in it's BIOS, and defaults to IDE devices getting the Primary status, not the SATA devices.
It's a HP Compaq dc7100 Small Form Factor PC... I thought it would be great for network file backup and very minor in-house HTML page serving, with between 1 and 3 machines ever accessing the HTML pages (Images with short descriptions, ala. Coppermine Photo Gallery)
for sharing the problem, since no error code that made sense was provided by the installer or at boot time.
At this point I just tried installing again, with the only relevant BIOS setting changed (combined vs. separate controllers)