Although stable version works perfectly, in 6-disks configuration (enhanced mode, 4 IDE + 2 SATA), and 4-disks configuration too (combined mode, 2 IDE + 2 SATA), all beta versions (681 - 683) refuse to boot.
They stuck at "trying to mount root from ufs:/dev/md0" message. CDROM boot fails, as does a previously upgraded stable 68. Regardless of HDs mounted.
M/b is QDI P4I865P, with P4 (HT) at 2.8G and 512 ram. I tested with two same m/bs, working perfectly with 68 and other OSs also.