When it’s a hardware problem, it’s usually more severe. You can tell it’s a hardware issue if the computer will not boot up or if it boots up with lots of issues. You may have to open up the machine and looking at what could be wrong. Getting a professional could be the best course of action.
Harsh environmental conditions such as extreme temperatures can damage hardware components. Unregulated power supply of any sort can damage hardware components. This includes power surges from the regular power line or from lightning.
A hardware bug is a defect in the design, manufacture, or operation of computer hardware that causes incorrect operation. It is the counterpart of software bugs which refer to flaws in the code which operates computers, and is the original context in which “bug” was used to refer to such flaws.