Having dropped into Antec recently (not literally, I used the lift), I noticed the company was preparing a thought-provoking demo PC - it was to show that even its TruePower 550W 80Plus Bronze rated PSU can power a system that includes a GeForce GTX 480 and Intel Core i7-980X CPU!
At idle the system used a not inconsiderate 172W of power, but under load that raised to 507W - still within the power rating of the PSU, although pushing it to 92 per cent use.
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Still, after playing with the system all day the Antec team claimed the setup was completely stable and even adding several hard drives and a few fans to this setup would still leave it under the full load mark, so at least you'd be getting your monies worth!
Obviously this leaves SLI out of the question, but after dropping nearly a ton on graphics cards you'd expect to be buying a beefier power supply anyway. Running the PSU "hot" when loaded will inevitably spin up the fan, but knowing the GTX 480s are modelled on aircraft engines (hot thrust out the back included), we couldn't hear the Antec running anyway.
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If you look carefully, you'll even see the Antec PSU can use the 4-pin and 8-pin CPU 12V power connectors on the Asus Rampage III Formula X58 motherboard underneath.
Power supplies are designed to be used in the 50-75 per cent load range for maximum efficiency, so while Antec's example just an extreme case - does it make a worthwhile point against the kilowatt bad-boys out there?
Is getting value for money and sweating PSUs to within an inch of their wattage ratting the future of PC design? Or do we need a better way to gauge component power use before purchase? Let us know your thoughts in the forums
The power use figure is the upper right hand number. Click to Enlarge