To the OP I suggest removing everything and making air clean the dust out

i have the same problem with my pc.. no beep, no display and my keyboard isn't on either(no power) but my mouse is fine.. I already did removed my RAM nothing happens still no beep? pls help..

One of the cuases is due to some dirts on LGA socket, so if you fixed your pc or removed your cpu recently you my find some dirt or dust on the LGA pins which can prevent some CPU connectors from touching the pns. This is happened with me where the screen was blank and there was not any sound at all even I removed the RAM just to listn to the fualt sound but there wasnt any.

Can you access the BIOS at startup?

What do you mean by over voltage what is over voltage

Got the same problem on a Toshiba laptop...

My PC power on six time beep and not display
What solution

Do a google search for beep codes for your specific computer (which you didn't bother to mention).