Do you have access to the rig or is it remote only? Sounds like a crash that only a hard power reset can fix. Update newest hive client don't use beta if you are, and you might have to loosen your OC more to keep it 100% stable.
I can access it - it`s my testing rig, where i test oc, change bios etc.
system stops just after HIVE logo with "Loading AMD Drivers ..." massage
soon after - Kernel Panic - not syncing: Timeout : Not all CPU`s entered broadcast exception handler