The 'last status' in 'Power on after power fail' item is selected and system shutdown normally with X7SBi. The system will power on automatically at power on next time. In the normal situation, the system should wait for power button be pressed.
The problem can be fixed by updating BIOS later than R1.3a. Please contact Super Micro support engineer to get the latest BIOS. (X7SBI_t3071.rom)
The BIOS will be uploaded soon to the following page.
http://www.supermicro.com/support/bios/