Internal V External Build issues

[HonorInDefeat]

I'm building my first PC by following along with this video (https://youtu.be/d_56kyib-Ls?t=14m48s). The video recommends assembling all the pieces outside the case first just to make sure all the parts work and mine do. I attach the Graphics card, RAM, CPU, Cooler and PSU together, make sure all the plugs are fitted right, and just like in the video I get the motherboard splash screen after about 8 or so seconds.

But when I reassemble the parts *inside* the case, no splash screen.

I've considered just transferring the MB whole into the case with everything attached but I didn't want to run the risk of breaking it before asking.

    
  
 Graphics Card-GeForce GTX 960    
PSU - CORSAIR CX series CX500 500W    
RAM - 1 x Pareema 8GB (2 x 4GB)    
CPU - Intel Core i5
MB | H81M-E35 V2

 

Edit: Ok, I got it to work. The only change I made was removing an extra MB braket that I had put on my case.


 

[Weak1ings]

if it runs outside your case it should run inside the case.  Just be sure you have everything plugged in correctly.  That is really the biggest issue I see rigth now.