*i don't know for sure if it's my motherboard or my case (switch)*

mobo: gigabyte ep45-ud3p
case: cm atcs 840

problem: when i press "power" the lights on my motherboard and the front panel (case) led's lights up as normal, as well as the case fans turns on as normal.

wait 1-2 seconds the led lights on the front panel and on my motherboard turns off, as well as my case fans.

wait 2 seconds everything turns on as normal.

q1: what could be the problem?

q2: what can i do to fix it?