So i built a pc yesterday with my friend and its worked until now i used my old parts and my motherboard has the green light on it but that is all nothing is turning on. I looked on my case to see if it was getting power and the red light isn't on. I tried to see if the led is broken on the case and i think it is when i connect the ethernet cable the light is on but when i held the power button on the case it turns off. Ive tried removing the ram and putting them in the other slots and removing the gpu and putting it back in. What is the problem?