Many UPSs do the job, but i suggest to go with APC as they are more reliable. mostly they are high end UPS, you have to go to your dealer and ask him, I am not sure that these facilities are available on 500VA UPS . These UPSs have Parallel Port/ Serial Port Connection to the PC, and when the power connection is gone they switch off the system.
Well known UPS brands like APC, Numeric come with a software CD, install the software
also connect your UPS with the cable provided to your PC. Yes, you can also configure
the software to shutdown the PC in case of a power failure.
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