motherboard problem- no power

[dingdowner]

Greetings all!
I have a major prob with my new build. 3.0Ghz Intel P4 in an Asus P4c800-E deluxe board. 1 gig of ram. Brand new 550watt ATX12v PSU.
My problem is that I cannot get to post. I cannot even get to boot as the 12Volt psu lead to the on board processor socket blocks any power up sequence.
with a basic setup- board out of the case, psu connected, ram and video card installed and KB, I cannot powerup altho Mobo led is lit. If I disconnect the CPU 12v power lead then Fans and drives and PSU fan will run using the normal front panel power button..When this happens, kb led flash, power led comes on and that isit. obviously,since CPU is not getting 12v supply so cannot proceed beyond here! Any guidance on what could be the problem or problems? Btw have checked and rechecked jumpers, reset CMos, removed battery once and have tested psu by itself.
grateful for any assistance Pls!

[Mick_D]

Let's start with something simple. First check the power supply's red tab and see if it's set on the 230V setting or the 115v. It should be on 115v if you are in the US. If that's not the problem please supply your complete system info. (Specific ram, video etc).

[dingdowner]

hi mick,
ram is crucial 512mb, brand new works in another machine so eliminated that.video is not an issue here since I am not trying to get a video signal ,not yet anyway. The major problem is with this flying 12volt lead from the PSU to the mobo processor (P4) socket. When it is connected the board refuses to power up anything except the onboard led. remove it and i can get cpu fan, drive and PSU fan working. Since no power goes to the processor, obviously i cannot beyond this point to attempt a post. latest development is that the PSU will not even power up. Suspect a rail has gon e even tho Spanking new. Another smaller PSU will power up fans,drive and board but has no 12volt lead for processor socket so am in a catch22 situ her
eric