While not high on the statistical probability chart, turns out both the SATA and Promise Raid card were bad- popped in a new RAID card and it's working fine, very quiet and no more worries about running too many drives off of one power supply without dedicated fans.
Broke again! Can you believe this? WD sells 400GB drives and Promise RAID cards bundled, BUT, the Promise RAID card will NOT work in a RAID configuration with the series of drives they sell in the same box! And this only took a gazillion reboots, two support calls with level one flunkies, three dropped support calls waiting for a level two rep and finally 2 minutes with the level two rep, enough time to say, "Serial #?. Sorry, no RAID for you!".
But wait, there's more- it may work, for a while, then not, then again, and so on. It is NOT supported, you're supposed to divine that the Promise RAID card should only be used as a two port SATA controller!!! How SLIMY!
The install doc does not say "RAID not supported, SATA controller only!" They deserve a big kick in the crotch. This config worked fine inside the PC for 6 weeks, before the external box was purchased. Never buying WD again, on principle.
We're taking the drives back, along with their crappy cards and have already purchased and are up and running with an Infrant 1TB NAS box w/ GB ether. Works like a charm, outta the box and as a RAID5, we get ~700GB of the TB usable plus hot swap!
Marketing slime gets moved up beneath meter maid in my most disliked professions.