Your power supply is shutting down to prevent an overload. Check your motherboard for "bad caps" if it's at least 3 years old; otherwise, get a better power supply. Do not go by the wattage; cheap power supplies are light in weight and overstate their load limits. I would use only corsair, antec, ocz, pc power and cooling, seasonic, or enermax. These power supplies are more efficient; look for a green rating of at least 80%. List your system specs including video card if you want specific recommendations.
 

leon2006

Distinguished
List down your system specs and power supply model/brand. How old is your pc?

Potential issues on your machines:

1) Overload condition due to a bad component on the load
2) PS Shutting down due to bad component on the supply
3) Overload condition due to lack of capacity of the PSU
 

pqlau

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Dec 8, 2009
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18,510

If i do the harddisk scanning, the power supply was also shutting down. Is it the same problem?