ASUS A7N8X Will Not Boot XP2400

[Bil]

I have a new A7N8X (not deluxe) with an XP2400 CPU and the system will not boot.

I tested the system with ONLY the CPU installed and the fan runs but there is no beep unless I remove the CPU. The heat sink IS correctly installed (with grease). The board does NOT shut down. Just won't beep with the CPU installed.

With a Duron 700 installed (and a very old PCI video card - my AGP won't fit this new type of AGP slot) it does start to boot, but there is NO VIDEO and no beep. A tech at Asus says the Duron 700 is not supported.

Does beep if I remove the video card. So it appears that the RAM (single stick of Kingston PC3200 400MHZ DDR 256MB) is not the problem since there is only a one second beep with RAM installed and no video card.

Power supply is an Enhance 300W (3.3V rated at 20A). I heard that you must have a beefy power supply or this mobo won't boot. But how much power does the XP2400 consume durring bootup?

[ski]

Did you clear CMOS by removing the CMOS battery, and repositioning the 'Clear RTC RAM' jumper?

After doing that, make sure the power supply's connector is fully inserted into the MB connector.
Then, install just CPU, video card, RAM(reseat it making sure it's fully seated), and monitor, and see if if there's a display.

If not, then insert the RAM in different slots.

If no luck, then place the MB on a piece of cardboard.
If that works, then remove all metal standoffs which are not lined up with MB holes, remove any loose metal objects under the MB, and reinstall the MB.
If no luck, then install paper washers(a manila folder makes good ones) between the MB and the metal standoffs and screws.

If no good, then try a different(borrowed?) power supply.

If still no good, then swap out the MB, CPU, video card, and RAM to find the cause.