Final answer:
To troubleshoot a computer that won't start, begin with basic checks like ensuring the power cord is connected, the voltage is set correctly, and the power switch is on. If these are not the issue, consider the recent hardware upgrades as a potential cause and inspect the internals for proper installation and connectivity.
Step-by-step explanation:
When a computer fails to start, it's similar to a car that won’t turn on; there could be a multitude of reasons. To address this issue, we can apply a systematic approach akin to the scientific method. Start by ensuring that the basic connections are intact: verify the power cord is plugged in, check that the power supply voltage is set correctly to 115V, and confirm that the power supply switch is turned on. If these steps do not resolve the problem, consider potential upgrades or changes made recently as they might have disrupted the system's functionality. From there, proceed with hypothesizing other causes, such as disconnected internal components or a faulty power supply unit, testing each hypothesis, and methodically eliminating possible issues until the root cause is found.
If basic troubleshooting doesn't yield results, additional investigation is required. A hypothesis, such as erroneously seated RAM or graphics card due to recent upgrades, can be tested by opening the computer case and inspecting these components. Ensure that all cables inside the machine are securely connected and that any new hardware is compatible and properly installed. Once a cause is determined and corrected, the computer should be able to start successfully.