Hello everyone, I need some assistance from someone here. I just built a new pc and it won't power up. I just bought a ATX case, a intel pentium 4 motherboard D915GAV with a 3.2 gig processor, 2 gigs of compatible memory. Everything is brand new except the power supply, I used an old one from another case. Now after putting everything together I notice that the led light turns on ,on the motherboard,so I take it that there is power going to the board. Now when I hit the power button to turn on the pc, nothing happens, the pc doesn't turn on, no fans , not even the one on the power supply comes on. I double checked to make sure the front panel was wired up correctly according to the diagram. The power switch,reset,and the led lights are all wired up correctly according to the diagram. The computer still does not turn on.I am thinking it might be the power supply but i am not sure because the led light goes on on the motherboard. Can anyone tell me what the problem may be coming from? . Oh by the way I forgot to mention that the case I bought did not come with a power supply, I used the one from the old case which is a Thermaltake TR2-430W. Is there a recommended power supply to power up an intel pentium 4 board running a 3.2 gig processor with 2 gigs of pc 400 ram? Any help will be greatly appreciated,maybe I overlooked something. Thank you