Anandtech checked out the Cooler Master V SFX Platinum 1100 PSU
A quote from the article:
Today were looking at a rather remarkable power supply from prolific peripherals producer Cooler Master. The company has put together a 1100 Watt, ATX 3.0 compliant unit that fits entirely within the SFX form factor for compact PCs. The resulting PSU is by far the most power-dense unit weve ever reviewed, and is a significant feat of engineering in and of itself.Cooler Master V SFX Platinum 1100 PSU Review
But Cooler Master and their OEM, Sysgration, are also testing the practical limits of the SFX form factor with their design. Even with no cubic inch wasted, regulating over a kilowatt of energy – and spiking as high as two kilowatts – is a lot of work for such a small power supply. So Cooler Master has needed to make some trade-offs here in terms of price and power quality in order to meet their overall power delivery requirements, resulting in a PSU that does well at delivering raw power, but its especially well-rounded overall.