Confirmation of power supply ratings

PSUs: The source of DC power for all components in the PC & often a big noise source.

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ChrisH
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Confirmation of power supply ratings

Post by ChrisH » Wed Dec 18, 2002 11:07 am

This article on overclockers.com measured the current draw used by a fully equipped system. It is one more bit of evidence that selling 400 W and 500 W power supplies for home computers is just a marketing ploy. A good quality 300 W system is fine for most home systems.

http://www.overclockers.com/articles668/index04.asp

MikeC
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Post by MikeC » Wed Dec 18, 2002 11:21 am

from our Recommended PSUs page:

Our own experience shows idle AC power conumption of 60~90W, and about 110~130W at 100% CPU utilization in several fairly representative mid-line test systems. Given the typical 65~70% effiiciency of a PSU, the DC power delivered is 40~60W at idle and 80~90W maximum. In other words, the amount of power actually required by typical desktop systems is about 30% of the capacity of the typical 300W power supply. Although some headroom is always good to have, most of us are paying for power capacity that is never used. One of the nasty side effects is the fan noise of high airflow required to keep the PSU adequately cooled when delivering maximum power.

Why this state of affairs exists is a matter of marketing and technical obfuscation, probably more by accident than any massive conspiracy.

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