boot up geta beep and shuts down

Most likely causes are:

Video card not properly seated or not recognized.

PC Health status error.

I have had many PC installations where the AGP card does not seat fully into the socket.
You can check this by removing the bracket from the card and seating the card into the slot. If the card seats deeper, then the motherboard is either setting to low, or the bracket was made a little on the high side.
I file the connector mounting holes in the bracket as needed to allow the video cardto seat fully.

As to PC health, if any monitored fan is spinning too slow, or the CPU core voltage is out of specification, PC health may activate.
Try re-setting the CMOS, and see if you can now get into BIOS settings to view the PC Health section.

I have also seen startup problems with SDRAM based motherboards not detecting the AMD CPU speed properly, and under-clocking the CPU.
For some reason, the AMD CPUs do not likelto be under-clocked.
I ALWAYS set the FSB and multiplier manually in BIOS settings.

Chas

Other possible causes could be the CPU may not be getting the correct amoung of power from the power supply.
Check the CPU and Power Supply,which should be a 300w,make sure that cpu is not overheating

You will want to check Video card, this problem might be a multiple agent scenario.

The video card may be causing the system to not boot up and provide display. The Power Supply Unit may also be causing the system to not boot properly because ifthe mainboard is not getting the proper voltage the machine will not proceed through the boot up process.

In order to get a better answer, you should provide the speed of processor, brand and model of mainboard and possibly the wattage of the Power Supply Unit. You should also explain what happened just before the system stopped working.

When troubleshooting the system, disconnect all unnecessary connections and leave only the main components, Mainboard,memory,videocard,power supply and processor. By limiting the components, your troubleshooting session should be quicker and more accurate. Also, try clearing the CMOS settings.

If you check memory, video and Power Supply and the system does not boot still, then the problem is more than likely with the BIOS (basic input output software) on the mainboard.