You have a hardware problem.
The best way to try to solve it is to make sure all connections are secure, the RAM is secure, and the video card is fully inserted.
If those are ok, then remove and reinsert the RAM a few times.
If no luck, then try the RAM in different slots.
If still no good, then remove all items except for the power supply, MB, CPU, case speaker, and power-on button.
If you do not hear any beeps during startup, then either the PS, MB, or CPU is bad.
They either have to be swapped out or shop tested to find the culprit.
If you hear beeps, then install the memory one stick at a time. If the beeps stay the same, then try a different stick or a different slot.
If the beeps stay the same no matter which RAM module or slot is used, then the RAM is probably bad.
If the beeps change after inserting the RAM, then insert the video card.
If the beeps stay the same, then the video card is bad.