Most motherboards will boot with the following minimum configuration:
CPU installed
CPU fan installed and connected to the power supply or motherboard, depending on the type of fan.
Memory installed
Display adapter
Power connected. Many ATX power supplies have a separate power switch on the back of the supply, which must be on. The 110/220 volt switch on the back of most power supplies must be in the correct position. And, of course, the power cord must be plugged into the power supply and a good wall outlet.
Power-on from the front panel connected (and the button pushed once).
Jumpers set correctly.
I also connect the loud speaker so I can hear any beep codes.