Why won't my pc start?

FlyingK

Honorable
Aug 21, 2012
14
0
10,510
So I just finished building my first pc and when i try booting it it won't do anything. The front light that shows if it's on lights for about a second then stops, and sometimes the fans spin for a second but then stop. I know everything is compatible so that's not the problem, my psu is brand new too so that's not the problem either. at first i had forgotten to plug in the 4pin atx 12v and it didn't work either but when I plugged it in it didn't do anything different. What could I be doing wrong?
 

FlyingK

Honorable
Aug 21, 2012
14
0
10,510
case: cooler master haf 912
cpu: intel i5 quad core 3.0ghz
mobo: gigabyte b75m-d3h
ram: 2 4gb sticks of corsair, ddr3 1333mhz not sure what the exact model name is
psu: corsair builder series 500w
no graphics card since the motherboard has integrated graphics, do I still need to connect the psu to somewhere on the motherboard so the integrated graphics work?
not sure what the hdd is but it would still boot up without it i think..
everything listed is new but the hdd that i took from another pc, but i wiped everything from it.
will try to add pics, but what should the pics show, the motherboard?
after reading my motherboard's instruction manual i found out that the pc would not boot if the atx 12v was plugged in and not needed, so i tried unplugging it and the fans spin when i start it up(they didn't spin when i didn't have it on) so I'm guessing i don't need it but my pc still won't boot up. Also, there was one place where i couldn't put a standoff so the motherboard has a spot with no standoff, maybe that causes shortages?
 

FlyingK

Honorable
Aug 21, 2012
14
0
10,510
well i just realised that when i plugged the atx 12v i plugged it the wrong way hahaha >.< i feel so dumb now... well everything is up and running the bios were corrupted but now they're okay