Hi,
A 4 beep error code is a memory problem.
Try re-seating the memory modules on the motherboard and check if that resolves the problem.
By that I mean turning off the PC and removing the power from the PC and then opening it up and removing the memory modules from the motherboard and then putting them back in again and then re-assembling the PC, reconnecting the power and see if it starts normally.
Here's the owner manual for the PC. Go to p.27 to view the necessary pre-requisite steps and then the procedure to remove/replace the memory modules.
On p.23 it shows how to remove the cover from the computer case and on p.21 it shows the location of the memory modules on the motherboard.
If the PC does start normally after having done this, if you have Win 10 installed run the Windows Memory Diagnostic and check the results. You may have a failing memory module.
crwdns2934105:0crwdne2934105:0
crwdns2934113:0crwdne2934113:0
crwdns2915270:0crwdne2915270:0
crwdns2889612:0crwdne2889612:0
5