What Happens when the PC boots up?”
What happens When a PC Powers-up? When you turn it on, a computer’s power supply must bring all the separate voltages required by the Motherboard and peripheral components to an acceptable level with enough current to power the whole system. These voltages include both + and – (plus and minus) 12.0 V (volts), + and – 5.00 V and most likely +3.30 V (which may be reduced even further by circuits on the motherboard for the latest power efficient processors). [ Note: All these voltages will vary slightly for each combination of power supply, motherboard, disk drives and various peripherals (since all electronic components drawing current will alter the power supply’s load), but they should never fluctuate by much (if at all) upon reaching their operating levels. If a power supply isn’t quiet enough (i.e, it has too much AC noise on any of its outputs), the motherboard’s BIOS chip may not function correctly; or more likely, the Memory portion of the Power-On Self Test will fail. Either way,
