As is obvious by the title of the review, this model is a 420 watt version. Something that is interesting in the build of this power supply is what Thermaltake calls Active PFC. It is basically the addition of capacitors within the unit itself. This causes a purer power flow when running your PC. Some PSU models can lose upwards of 50% of their rated power flow but the Active PFC used in this model allows for a power frequency that is between 95-99% of its full rated output. This will allow you to run more peripherals, drives, devices, fans, lighting modules; pretty much anything you want to run.
Another nice feature of this model is a dual fan setup. And to make things even better, both fans are ball bearing type models so they'll have a longer life span. But don't let this fool you into thinking that you can cut out some of your case fans. Their purpose is to keep the PSU cool and running smooth. They are not designed to make a significant difference in your case cooling.
But in case you're wondering if this will create a lot of excess noise with the two fan layout, let's take note of the fact that the fans are temperature controlled. Located within the PSU is an independent thermal probe that is used to adjust the fan speed of the unit. At a temperature of 25C the fans spin at a meager 1300RPM. This figure goes up considerably if the PSU starts to run hot. It will max out at 80C with a speed of 2400RPM. Though I do not have specific decibel ratings for this power supply, the noise level is very low. Without any other fans running it is whisper quiet.
One final feature worth noting is a safety device that has been incorporated into these power supplies. It is called Over Voltage Protection and works in a similar manner as a circuit breaker. If the voltage level on any of the power rails exceeds a set upper limit, the PSU trips into an off state. This will help make sure that your precious components don't end up going to computer heaven too soon. Here's a quick list of the set limits:
It is just a little insurance for your system. After all, when we build our own rigs, many of the parts we get for it are rather expensive. This will help make sure that they live a long and healthy life.