According to this link the pattern (Long constant beeps) indicate is a system memory problem. Try reseating the Memory Modules (RAM) in the computer and see if the issue is fixed.
Note: Reseating the Memory Modules (RAM) requires you to reseat the component by removing the system cover/taking apart the chassis. Please perform these steps only if you are comfortable else seek a technician's help. Also, refer to the Service Manual for accurate steps and safety instructions.