Try a BIOS recovery with the most recent BIOS available
Three beeps sound means a memory issue so my recommendation is to try just one memory stick in one memory slot. Another good step is to try another memory part number or brand as much as possible.
It is important to say that the memory specifications you need to use is 1600MHz at 1.5v.
You can also try as part of the troubleshooting steps, another processor just in case the memory controller in the processor is failing.
dear sir, thanks for your reply,
I also try the troubleshooting steps, but still beep sound only not booting.
Is it a motherboard problem? or processor problem? pls replay.
My motherboard is INTEL DH87RL
Processor is INTEL Core i5 4440
i replace my motherboard, thanks