If you have more than one memory stick installed.
remove all but one.
Then try to bootup
If it still doesn't work switch the memory to another stick.
If you don't have more than one memory stick to use for testing you need to replace what you have
If the system will give a post code ( beep) it should be bad memory NOT the cpu.
A doa cpu will the cause the system to fail with no post (Beep)