Depends on the size of the computer power supply, and CPU, Memory, Video Card, and so on. I'm guessing 1,000VA would be around 650-700watts, well unless someone revoked Ohms law anyway.
If you simply want to shut down, and save data, perhaps two might remain powered up for ten minutes, One 20 minutes. Also what else is being supplied via the UPS? You will need to keep your monitor(s) on, Suffice to say "Not very long".
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Depends on the size of the computer power supply, and CPU, Memory, Video Card, and so on. I'm guessing 1,000VA would be around 650-700watts, well unless someone revoked Ohms law anyway.
If you simply want to shut down, and save data, perhaps two might remain powered up for ten minutes, One 20 minutes. Also what else is being supplied via the UPS? You will need to keep your monitor(s) on, Suffice to say "Not very long".