The power supply market now has a variety of different models produced, the one does not have dreamed a few years ago, along with this great selection to the potential buyer is of course something of a challenge, namely to find the perfect model for him. Besides the "standard" class in the range of 400 watts and the high-end power supplies in the range of about 800 watts, there are also interesting and powerful examples in between, in this review we shall therefore look at three power supplies in the range of 610-650 watts even closer.

Fasting would be considered a maximum of 400 watt power supplies with the most interesting test candidates, because they can easily operate the vast majority of PC systems, you should limit this statement, of course, on power supplies from renowned manufacturers, because unfortunately there are enough copies on the market, where the whole energy of the hot air and the manufacturer's marketing department has been inserted. Coated high performance data combined with a low price to attract the buyer, and in most cases the computer will run well.

Another point that speaks for the 400W class is, of course, the recent advances in processors and graphics cards, the 45 nm Intel processors manufactured and the current mid-range graphics cards from ATI and NVIDIA can put together powerful systems that receive significantly less compared to previous technology performance. But when it comes towards overclocking, extensive peripherals and possibly direction Crossfire / SLI, though not without buying a more powerful power supply is recommended, for example, a range from 500 - 600W.

With the here tested power supplies in the range of 610-650 watts on the other hand, systems with quad-core CPU and two 8800 Ultra graphics cards in SLI setup are possible, for Triple-SLI and massive overclocking should be then but on the other hand, the high-end class in the range of 800 watts or more.

For the dimensioning of the power supply, there are different views, some think that you should size the power supply is just large enough, the others are of the opinion that much too much help, the truth probably lies in between. Happy to be noted that a "requested by" power supply has a worse efficiency in operation, as one that is polluted well, this is the usual case with power supply, but the field of demand is usually just under 20% utilization.

If a computer system in the idle state, for example at 25% utilization, it has in modern power supplies de facto no longer disadvantages. The other way is considered to be possibly a slightly oversized power supply is even a disadvantage, because the efficiency of power supplies is usually in the range of approximately 50% of its maximum load, then it falls back slightly.