My asus p5n-E sli motherboard just beeps when i turn the computer on, any ideas?

The beeps are post during post the very first work is done by the ram,all the memory in the ram is first transferred to the hard disk,and remains active untill turned off.

make sure that your RAM and Cmos battery are securely seated

Test all leads that attach to your hard drive including electrical extensions,IDE,SATA

the leads from your ((motherboard to your hard drive)) make sure they have a secure connection and are not faulty or just replace them they could be faulty

a computer needs its connections to continue its cycle and to have and end to function
the beeps are post pre operating system searching for some hardware it could be RAM cd/dvd hard drive or motherboard all of these must have secure connections for the computer to work
make sure all leads that are attached to your drives dvd\cd 3 1/2 inch floppy have secure make sure the connections and are not faulty even the electrical extensions or just replace them they could be faulty a computer needs all electric current and computer data to travel to and through every working device and have an end to work properly click start right click on my computer so any faulty leads will end up with a computer error
hope this helps you