So i just built my first computer, and before putting it into the case i put it on my motherboard box and test booted. i successfully booted into the bios. then i put it in my case and i pressed the power button...and nothing. no mobo leds or anything. i tried to reseat the psu cables, both the ones on my modular psu and the ones attached to the motherboard and the graphics card, and i also tried to remove the power button connectors and tried to jump the cable on my own. the only thing i saw flashing on my mother board was the FLASH BIOS button on my tomahawk max when i pressed it. also i did the paper clip test on my psu and confirmed it was working, but the fan doesnt spin when i connect it to the motherboard. i disassembled my computer again and am now back on the motherboard box. still no luck. please help because i have no idea what to do