Start up Problem, Please help

[grzesiu]

I have just finish building my new PC, Intel D925XECV2 MB, P4 3.0, 1 gig ram, Antec 430 PSU.
The thing will not boot, and the wierdest thing is that when i connect ONLY 24 PIN power to my MB (without 12V 2x2 PIN) the thing powers up, all fans are spinning, HDD is turning, CPU fan is turning - BUT nothing on the screen, no beeps, and there is no way to turn it off, except cutting power off.
OK, (i know i have to plug in 12V), so when i plug both, 24PIN power and 12V 2x2 PIN and press power button, NOTHING happens fans not turning, like there is no power at all. Wierd thing is that the power LED lights up, and when i press power button again it disseapears. The power supply is fine, i have tried 500W new one, and it did exactly the same. I doint think it is memory either, because i took the memory out and i did exactly the same thing without the memory.
WHAT CAN BE THE PROBLEM???????
I has power but no boot with 24PIN power connected ONLY, but no power at all (except Power LED) when 24PIN and 12V 2x2 are connected !!!!!!!

[Paleo Pete]

First thing to check is for a ground problem. Remove the board from the case and hook it up on a tabletop or some cardboard, (it just has to be non-conductive) and plug in only CPU/heatsink, RAM and video. A keyboard might be handy if you want to look into BIOS but is not necessary. All you need is to see a picture. Find the power on jumpers and short them with a screwdriver briefly to turn the machine on, unplug it to shut down. IF you get video, put it back into the case and try it. You migth have to stand the case on its side or pull the power supply to get the wires to reach, some don't have very long leads.

If you get no video again after putting the board back in the case, it's a ground problem, you'll need some cardboard washers under the screws that hold the board to the chassis. Test both situations with only the bare bones setup, motherboard, CPU/heatsink, RAM and video card. That gives you less hardware to troubleshoot if you still get no video. In some cases the washers have to be put under the motherboard, but usually between the board and the screws does the trick.

[grzesiu]

Thenx for the help. I did what u told me, but it didnt work, still the same problem. I think the MB is broken, i even put a new CPU, the same problem, power with 24 PIN, nothing with 12V :(