(Time sensitive) when clicking the power button the fan moves a bit but does nothing else

[minepug268]

I just finished repairing a DH55TC Intel pc but when I click the on button the back fan moves a tiny bit than it doesn't do anything else. Did I do something wrong? Another thing is the power light only turns on in the red slot when the red alot is for the on switch

 

[kanewolf]

Why don't you describe what you did to "repair" it, maybe that will give us some idea where you might have a problem.

 

[kanewolf]

MERGED QUESTION
Question from minepug268 : "Please help. My computer wont power up"

I bought a computer from someone for really cheap to run some basic programs 24/7 and at first it wouldn't connect to the display so I took all the wires out and plugged them back in. I think I screwed up. When I click the on button the rear fan spins a bit but it instantly goes back.