Did some research on the throttling down to 1.9GHz, and it seems the stock cooler simply isn't good enough to handle all cores on full load. I'm experimenting with some water-cooling at the moment, I'll post my results when I'm done testing. Might even try to OC the bastards if temps look good :P
RE: I Just Wanna BOINC! -- Part 3: Alternative Single Board Computers