Three beeps that repeat after a pause and occur when you power on your computer indicate a problem with the system memory. Three beeps that play and then stop as the computer starts successfully mean that the BIOS was restored.
Try lipat lipatin yung memory stick kung meron kang dalawa or kung isa palit palit slot. Discharge pc psu, ipahinga tas umasa na magbubukas pa siya baka napapagod lang at gamit na gamit hahaha