Cache Test Failure..

4 beeps during boot up indicate a memory failure.  You either have defective RAM or the wrong RAM installed.

Try this.  open the case and remove all the RAM form the main board.  Pick slot ZERO and plug it in by itself.  It looks like this board has 4 memory slots, two with white tabs and two with black.  The board should be marked to indicate which slot is the first.  it's usually labeled as "slot 0".  If you cant tell just pick the white one closet the the CPU.

If the PC still won't boot try the other white slot.  If they both fail then try the other black tabbed slots.  Eventually you should get the PC to boot although you may need to boot into the BIOS each time to allow the PC to detect the change in RAM.

Once it boots, add another stick of RAM.  Put it in the same color slot.  If it boots OK then swap one known good stick with one of the others. Do this until you find the bad one(s).  You'll need to buy 2 new ones since they go in in pairs.

If all this still doesn't get the system booting there might be a CPU problem or the main board itself could be dead.  Obviously these would require spare CPU and board to swap in so at this point it might be worth a trip to a shop, or a new PC.