Performance of the Hydro PTM 650 W is high enough, although it could even be higher if the transient response on the minor rails were better and the hold-up time a little longer. That said, this is an efficient and silent power supply under even tough conditions nonetheless. In fact, this is one of the quietest PSUs in the 650 W category, losing only to the RM650x, which is less efficient, and the Formula Gold 650 W Bitfenix, which features a non-modular design.

What needs immediate attention is the cable hosting both EPS connectors. It might be an asset that this 650 W unit comes with two EPS connectors, but they should be installed on separate cables since they can draw lots of power. A single connector on the PSU and the 18AWG gauges won't be able to cope if both EPS connectors are heavily utilized. Now, if you don't plan to go crazy on these connectors, it is incredibly nice to have them.

The Hydro line consists of good and reliable PSUs that are covered by a hefty ten-year warranty. The pricing scheme is also fair, but in my opinion, FSP should lower its prices a bit to compete with the popular Seasonic Focus models since the Focus models have a killer performance per dollar ratio. I know that it is very hard to beat Seasonic's highly aggressive pricing scheme, but this is the only way for FSP to claim a notable part of the sales pie.

FSP might be one of the largest PSU manufacturers, but its retail department is not that large. In my opinion, this company's decision makers should invest more resources into retail sales while pushing for good designs and platforms more, like the one used in the HPT650M. In a market where Corsair, EVGA, and Seasonic dominate, alternative options which easily manages to stand out from the crowd due to their external design are nice to have. The HPT650M surely deserves to be included in your list if you are searching for an efficient and silent mid-wattage PSU for your system. The two EPS connectors allow for compatibility with high-end mainboards as well, but you have to be careful not to overload these as you will most likely face problems with molten connectors and wires otherwise.