How does a modern computer react on a fluctuating voltage?

Question

At what voltage does he shut's down? Or how high can it go?

Answer 1

If the voltage rises and drops your computer may lockup, restart, or burn up your internal components. I suggest you get a battery backup for your computer they not only protect against power surges but they also compensate for power fluctuations.

Answer 2

If the power souce flucuates, this is bad. I've often heard people refer to this as "dirty power".

I'd like to say the 1st poster's comment about build in battery supply, 99.999999% of computers DO NOT have a built in UPS, and even if they do, it's most likely and offline UPS, meaning the UPS is charged bu the computer switches to it if the power goes off. Even though the computer plugs into the UPS and the UPS plugs into the wall, it's still an offline UPS.

An online UPS is the best option as the PC only draws power from the UPS and the outlet charges it back up. These will often be much larger than an offline UPS.

You best option is to use a high quality PSU (power source unit) in your PC, I can't think of any name brands except for Enermax but there are better ones. Better PSUs can level the power out.

The problem with fluctuating voltage is that it will wear your PSU out quicker, and possibly your PC components.

Answer 3

you say modern computer!
this is no more a problem since the beginning of this decade. i have a power supply (already 7 years old) that works flawless for an input voltage of 100 - 240V (without a switch for different voltages like US and Europe).
i think the computer even works for an input voltage down to 90V. for the upper limit it may have an overvoltage protection (not sure about this).

Answer 4

some of the new ones have built in battery backups/surge suppressors. how high it can go depends on the power supply, but generally 120 volts is the limit