Power Requirement for Asus GTS450

Your power supply has enough wattage, but is the quality good enough?

It's always good to upgrade to reliable power supply if you have money for it. Thing is, non branded power supplies tend to have cheap components inside them and if they fail, they may damage other components. However, quality power supplies from reliable brands tend to provide protection from high current, high voltage, and failing. That means, even if it fails, it will not damage your other components.

Read this:
http://www.tomshardware.com/reviews/low-cost-psu-pc-pow...

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400w (non-generic) should be enough for GTS450