Our load tests utilize a couple of FAST ATE active load testers and a variety of other equipment such as an oscilloscope, power conditioner, temperature probe and a power consumption meter. You can read more about our standard testing approach here.
The tests performed are based around six conceivable setups that are out there and progressively load down the PSU up to the power supply's limits or 1000W, whichever comes first. Since our test equipment's limits are greater than the Scythe Kamariki 4 650W PSU, we can test it to the maximum.
While the Scythe Kamariki 4 650W power supply passed all four of our tests, it did so just barely. In fact, it couldn't have come any closer to failing due to the voltage on the 5V rail at maximum load. If it had dropped just another .01V, it would have been outside the ATX specifications. Things weren't looking that great on the 12V1 rail either, with a reading of 11.60V at maximum load. However, when it's all said and done, a pass is a pass.
The Scythe Kamariki 4 is a beautiful unit with plenty of features for a mainstream power supply. It has several things going for it such as aesthetics, modular cabling, plenty of connections and cables, and the ability to control fan speed via the built-in controller.
However, there are a lot of things that the Kamariki 4 just doesn't have going for it as well. Internal packaging could be much better, Taiwanese capacitors, and nearly failing voltages just don't cut it in the cut-throat mainstream market when power supplies of similar wattages, features, and perhaps better quality can be had for as much as $30 less with longer warranties.
As a mainstream PSU, the Kamariki 4 certainly is acceptable, but other existing models that we have tested are superior since they offer lower cost of ownership and better performance.