Several systems based on the X7SBI-LN4 motherboard cannot boot up with only 1 CPU and 2 memory loaded; however, when I put the motherboard back in the chassis, the system powers up normally. Everything is the same except there is a CD-ROM connected in the chassis. Power supply is FSP460-60 PFN.
Some particular power supply may need a minimum loading for operation. When loading is not enough, the system can not power up.