URGENT HELP for AI7!!

I've just built a new rig with AI7. When I power on the system, some "ambulance sound" come out immediately. The POST Code changed quite fast and finally stop at 25. Then the system did nothing but gave the "ambulance sound".

Here is the description of POST Code 25 from AI7's manual:
Early PCI Initialization:
- Enumerate PCI bus number.
- Assign memory & I/O resource
- Search for a valid VGA device & VGA BIOS, and put it into C000:0

What's wrong? What should I do? What can I do? I'm feeling extremely depressed.


Components of the rig:
New components: AI7, 3.0C, Patriot PC4000 512MB x2, Hitachi SATA 7k250 160G, Winfast 6800
From old rig: WinTV250, NEC 1100A DVD/R/RW, Pioneer DVD-ROM

make sure everything is plugged in correctly. a loose component can cause weird stuff. if not then just use 1 stick of memory and the video card and see if it boots..
also reset bios if u havent done so..

The "ambulance sound" can be CPU fan not working or not connected or CPU heatsink not installed correctly. It can also be just a low default CPU temp alarm setting in the BIOS.

That's the alarm that can be for low fan RPM, high temp, or voltage out of spec. I would look at the CPU fan first. If you are using a 4 pin molex instead of the mobo header or watercooling, then you will get that alarm. Even if you have the CPU fan plugged into a 3 pin connector on the mobo, if it's not plugged into the one marked "CPU" the BIOS thinks you screwed up. You can disable it in the BIOS.

I just reread your post. It looks like you can't even post or get into the BIOS. If you have a vid card that requires a separate power connection, make sure that's attached. Reseat the vid card and RAM. Make sure the RAM are in 1 and 3 slots or 2 and 4 slots (same color slots).

Thank you so much guys...
Problems solved!
Yes, I didn't connect the CPU fan to CPUFAN1.
And yes, I forgot to plug the extra power for the video card.