I can't say the Dagger Pro with 650 W maximum power output managed to impress me, although its build quality is good. There are two EPS connectors, which is rare for SFX PSUs, and it has a pretty long hold-up time, along with a tight load regulation; still, its performance is not on par with the competition. Even FSP's own platform with the same topology (ACRF), used by the EVGA 650 GM, performs considerably better. Apparently, the Dagger platform was developed by another team of FSP engineers, and they didn't bother implementing some of tips from those responsible for the platform used in the 650 GM. The best and probably less expensive solution would have been to use the same platform in the Dagger Pro. If there is an exclusivity deal with EVGA, they could always modify it slightly.

The SDA2-650 isn't only expensive but also noisy, especially under high loads and increased operating temperatures. Its transient response is mediocre, and the efficiency of its 5VSB rail is incredibly low. The small number of peripheral connectors pose another problem. Five SATA and two 4-pin Molex connectors might not be enough for some users as this is a strong high-end SFX unit and would most likely have to cope with a large number of peripheral parts, like AIO cooling solutions and fans.

The issue that troubled me the most is the wrongly configured OCP at +12V, which also affects over power protection. Once I increased the load at +12V, the load regulation on this rail went south, dropping to dangerously low levels. Protection features exist for a reason, and every manufacturer has to set them properly, not only to protect the power supply but also the system it feeds with power. Allowing any of the rails to drop too low exposes all parts to danger because the system's regulator circuits cannot cope with such low voltages, which also puts a ton of stress on these circuits. Believe me, you don't want your incredibly expensive graphics card to drop below 11.4 V signals. Of course, the same goes for the CPU's phases and all other parts of the system.

FSP has to take a look at the issues I highlighted in this review, and should fix them by going over the design—the sooner, the better. With the necessary know-how (a bright example is the EVGA 650 GM model which uses an FSP platform), doing so won't be hard for their engineers. Its two EPS connectors are the only reason I can think of for going with the Dagger Pro 650 W over the EVGA 650 GM since EVGA's PSU only has one EPS connector.