The most common issue with a CPU is when it isn’t installed properly or securely. This could possibly cause a complete failure when trying to turn
on the system. This failure could be accompanied by a series of beeps from the POST. If this happens, always check the power first, just in case.
Another possibility is that the system will turn on and power will be supplied to the system, but nothing else will happen: no POST, no display,
and no hard drive activity. In any of these situations, after checking power, make sure of the following :
Check the big four
Fan is connected and functional:
Heat sink is connected properly:
CPU is installed properly: