I have two 1600W server PSU's for the cards (6 on each) one 850W EVGA ATX with one card / riser.

All using 6-8pin, risers are split once (1 cable per 2 risers)

Any chance it's a memory issue? I am running 4GB, my memory says 3.2GB / 4GB in use (85%).

Since disabling watchdog, it shouldn't be a server issue. The miner would just keep trying to reconnect.